To clarify: the reason for the hiss in position 0 is because the vacuum pods have failed. It is also a possibility for this to happen with the vacuum lines at the switch are installed the wrong way around but this was not the case. The pods have 100% failed. They were tested off camera and were blown out exactly as per the demo on the red car. This must be a common fault. Position 0 closes off outside airflow position between 0 and 1 allows outside airflow without the fan operating. This would be useful if travelling behind a smelly vehicle when airconditioning / heating is not required. Given that my car is not a daily driver the loss of this feature isnt life altering.
very informative video! I now can replace mine if i can find the proper parts. the fan speed switch in my w124 has a similar issue: speed I is completely gone, but luckily speed II, III and IV are still there - and yes, speed II is the most used fan speed, I guess the contacting point is bad..
I Give Thanks For Your Hard Work ..And The Knowledge You Give To Us .. Am Owner Of W124-36 E500 ,And I Have The Same Issues AC Switch ..Again Thank You ..All The Best Cheers.
Hi! Aircon was working great then all three middle aircon buttons LEDs stop lighting up and air blowing out isn't cold any more. Would this be the buttons working? Changed fuse 9 and no success (unless that's the wrong fuse) Thanks
The 3 push buttons have 3mm rainbow colour changing leds for backlighting. I just installed them in place of the original yellow ones. I also changed the pilot leds from red to green for the buttons. I am a peculiar character.
Hi nice video, i have w124 also, the bulb in the fan knob not light up, i tried to open the knob but it was hard to open. Is it mine cannot be open? The air distribution knob(right) is easy to open. Btw what watt is your led in the console? Many thanksss
Abdul Azim Abdul Salam the fan speed knob bulb holder turns with the knob so its not unusual for the wires to break internally eventually. It is possible to repair this. I have done it before, just not videod it. Not sure what you mean about leds
Hello. I have a problem with this system. I have a Mercedes-Benz 2.5 D Wagon. Frame position in the video 1:18. When the key is in position between 0 and 1. The car's engine shuts off normally. But when the fan switch is in position 0. The engine is very difficult, or can not turn off. Do you have any idea what the problem is, and what needs to be replaced or repaired? Thanks in advance.
Do you perhaps know what the bulb code is for those LEDs? Before my interior was taken apart, the left side switch light was dead and I could never find any replacement bulbs mainly because no one knew the bulb code/number.
They are just t5 wedges, incandescent versions come in different wattages depending on application, using the wrong one results in melted plastic. Using LED’s solves this concern and they last basically forever. As with just about everything else i buy, they came fron eBAy.
@@MMWA-DAVE yes does not turn to all 4 settings.. just .. just not sure if it’s a switch issue or if it is more sinister that that as it seems like it has a mechanical connection .. and is not an electrical switch.. 🤷♂️
@@seang2822 It can either be the switch mechanism or one of the flaps inside the airbox has jammed. Not a nice situation to be faced with. I would swap in another switch mechanism first as it’s easiest. Airbox repairs are a complete nightmare.
@@MMWA-DAVE thanks.. I heard the whole ac/ climate control system can be very expensive to fix in these cars .. and am dragging my feet to delay opening a potential can of worms 🤦
Hello. The middle bulb of the right knob does not light up, everything else lights up, the bulb itself is not broken, where is the problem? I hope you can help me.
Hi, i have a AC dilema, i need to know what Part Number is written on that ac control panel, i cannot seem to find a good wiring schematic for this type of AC, i mean heater core has only 2 way switch over valve, not 4, not 7... and if i put DTC tester on car, i get 58 blinks witch means that valve block (4 connections) Y11, short-circuit or open. Can you help me please with that part number, or a wiring diagram that matches your AC system please? Thanks !
as far as im aware - no electronic version of the wiring diagram exists for this type (tempmatik) I have never had one. I’ve only ever seen it in the paper w124 service manuals. (which i also don’t have) The Australian version service manuals have it, the USA version manuals which as usual are all over the internet, do not. Part number of my panel I can give later, I have several spares.
@@MMWA-DAVE i was looking at older videos, and find a part number here, ua-cam.com/video/PUbubrg8or0/v-deo.html , can you please confirm that this is the ac panel of the car with only 2 way switchover block ( i mean the car in this clip )? 1147328524 bosch and 124 830 19 85 mercedes PN. Thanks again. I have some AC wiring if you want them, i can give it by mail. Have a nice day :)
@@drideanugabriel2098 all Australian version w124’s have duovalves. Later have the later version with integrated pumps. Be aware though, there is an even earlier version control panel if your car is a very early version. The electrical socket on the rear is different and physically will not plug into this version harness
@@MMWA-DAVE Yes yes, i know that they have duo valves, but i was talking about the switchover valve block, that actuates the vacuum pods from heater box, here take a look at your video ( ua-cam.com/video/MelDNbPAdEA/v-deo.html ) min 4:11 you will see the switchover valve block that i was talking about, so to clarify the situation, i think my car has a newer AC panel, why? because if i scan it will give me that 58 blinks error, i see that you car has same heater box system as mine does, and i think that your ac panel is correct for my car also. Later models came with diffrent switchover valve blocks, some came with a 4 way valve block ( noted as Y11 in wiring diagram ) and later one came with 7 way valve block ( noted as y7 in wiring diagram ), i think my system and yours is something inbetween those changes, there is also a earlyer system noted with y13, our system works with Y13/1 switchover valve. So if you put a newer ac panel in your system, if you test it with diagnostic tool, it will give you some weird errors that shouldn't be there, I know i'm not explaining very well, i'm sorry. I hope you understood something :)
My 300ce has always hissed if I don't leave the knob set between off and pos.1, will have to change the switch now I've seen it. I still don't quite understand why an electrical fan speed switch has a vacuum connection though?!?
Matt Teee its not the switch - the hiss is because the vacuum pods have failed. The reason for the vacuum connection is so outside air is sealed off in position 0 and fresh air is allowed in with switch between 0 and 1. As you can see from the video they are not easy to access with the dash installed. I wont be changing them on the blue/black 124.
Do you have any idea of how to work the fan control switch so it turns on & off with the ignition key. If I lock the car after turning off the ignition & leave the fan on a low setting, I can come back to a flat battery, which has happened. If you can come back with a way to control the fan switch with the ignition, I would be most appreciative........to anyone!
the fan should only operate in key position 2, you have an electrical issue if it is operating without the key. Unless you have remnants of the optional independent fuel burning heater malfunctioning. That option was available in cold countries.
@@MMWA-DAVE Yes, I know the fan should only work in the accessory ON position but it has been hard wired into the No.10 fuse....heatable rear window....& when you take the fuse out, the fan blower does not work, along with the heatable rear window. This fuse is obviously not controlled by the ignition key curcuit.What fuse is it wired into & on a second issue, how do you pull the two knobs off the update model to gain access to the hazard warning switch which is U/S in my car? Mine won't pull straight off & as you said, no screws on either side of the radio either. Thanks, Rick.
@@nickhighman4455 I think I know what's going on here. On the later models there was an issue with the fusebox melting specifically at the blower motor fuse. I suspect someone has done a very imperfect repair and tapped into another circuit. The correct factory approved repair method was to disuse the original fusebox location and hard wire in an external fuse holder. It is supposed to sit outside the box. If it was my car I would be opening up the fuse box and trying to establish what the hell has been done, finding the correct external fuse modification from a wreck or wiring in an alternative external fuse. If your car has the manual 2 zone system like mine with the knobs they simply pull off. Under them it is very self explanatory with big nuts that need to be removed on the knob shafts themselves. The shafts then click out sideways. The late cars as you say wont have the screws near the radio so the wood will just pivot upwards once the knob shafts are free then you have access to the hazard switch. I am unfamiliar with the automatic push button system if that is what you have.
@@nickhighman4455 In answer to your question also, on my car the blower motor has its own fuse - fuse 12. So some investigation is required under the fuse box to see whats happened / been done.
@@MMWA-DAVE Absolutely right. I've just talked to my son who confirmed the original owner of the car here in Toowoomba, had issues with the blower motor fuse melting & had the Green/Black wire from the blower motor hard wired into the underside of the fuse box at position No.10 (a fuse that's for the rear window demister & controlled independently of the ignition switch) I've pulled the fuse box apart & there at No.10 is the elusive wire, that, when wired directly across to the battery, runs the blower motor. Now I just have to pick up a power wire from the accessory side of the ignition switch & problem solved. The external fuse is a damn good idea. Thanks for all your help with this matter, now for the next big issue........getting those two knobs off the air con. rotary switches so i can get at the hazard switch. At the moment, they just won't come away. And yes, mine also has the manual 2 zone system but they just won't budge. Much appreciated for you help in this matter!
Hi..i had issue similiar like this, it start at speed 3 but if 1 drop it to speed 2 or 1 it will off and then i can hear sound inside the console like "krak krak krak" like ac fan wheel but i dont know Do you know what it is?sorry to bother you and for my bad english..thank you sir
Hello, I have an issue with my 300e 24, when I activate the level 3 or 4 of air fan, few time after it stops. Then I check fuse 12 of fusebox and it's completely melted... Any idea what could be the problem? Kind regards!
Dj Campos Chinese plastic fuses are rubbish. Purchase ceramic ones with brass/copper fuse materials. They are available online from Europe. If the fuse is still blowing at these speeds the motor itself may be starting to seize or the fuse holder is the issue. But absolutely do not use cheap plastic fuses.
@@MMWA-DAVE When I bought the car (2 years ago) all air levels (1 to 4) were working correctly and fuse 12 didn't weld...So I think I have an issue, one friend told me maybe was the potentiometer of the level selector. But I think the problem is maybe that current (A) it's too high (maybe air fan it's skimming with something and that's why it has overconsumption). I don't know how to diagnose this .. 🤔
Dj Campos this is another job for a multi-meter - if the one you have can measure amps that high. Most likely not though. The fan motor bearings do seize with age and if the motor is getting tight to turn it absolutely will draw excessive current. The fan switch has nothing but contacts in it. Its just switching between coil resistors up on the firewall under the windscreen in a metal cage. Position 4 straight battery voltage is going to the fan and position 3 the lowest amount of resistance. I only ever operate my fan at position 1 or 2 if the airconditioner is working well you dont really need the upper speeds and Western Australia is as hot as hell in summer.
@@MMWA-DAVE Well I also would like to use air conditioner but it doesn't work too ☹️. Last year I paid 330€ to mechanic and he did nothing. Air conditioner still not working... And it can be because of lot of things so...
Dj Campos with the age of these cars the ac system almost certainly needs to be completely rebuilt- this is cost prohibitive to pay someone to do so i did it myself. My blue black car’s ac has worked perfectly with no leaks for 5 years now. I will also be doing the same on the red project when the engine is back in and running I already have all the parts
When you hold at 2:39 you can see the main 3 buttons for the AC, starting by lowest button which is the air being recycled or not, the middle one is the AC button itself and then the one that comes in first place, does anybody know what that button for? I need to know what is it please
mohammed jamal top button runs the compressor regardless of the interior temperature. Its for defogging the front window. I use it all the time to keep the airconditioner lubricated in winter time.
To clarify: the reason for the hiss in position 0 is because the vacuum pods have failed. It is also a possibility for this to happen with the vacuum lines at the switch are installed the wrong way around but this was not the case. The pods have 100% failed. They were tested off camera and were blown out exactly as per the demo on the red car. This must be a common fault. Position 0 closes off outside airflow position between 0 and 1 allows outside airflow without the fan operating. This would be useful if travelling behind a smelly vehicle when airconditioning / heating is not required. Given that my car is not a daily driver the loss of this feature isnt life altering.
I got the same hiss in position 0
very informative video! I now can replace mine if i can find the proper parts. the fan speed switch in my w124 has a similar issue: speed I is completely gone, but luckily speed II, III and IV are still there - and yes, speed II is the most used fan speed, I guess the contacting point is bad..
I Give Thanks For Your Hard Work ..And The Knowledge You Give To Us .. Am Owner Of W124-36 E500 ,And I Have The Same Issues AC Switch ..Again Thank You ..All The Best Cheers.
Take care of that magnificent vehicle
MMWA Always It’s a Great One I Do Love It .. This Vehicle Since Made Am The 2nd Owner Since 1999 ..
those cars are rare
Hi!
Aircon was working great then all three middle aircon buttons LEDs stop lighting up and air blowing out isn't cold any more. Would this be the buttons working? Changed fuse 9 and no success (unless that's the wrong fuse)
Thanks
6:00 Holy LEDs Batman! Lol
The 3 push buttons have 3mm rainbow colour changing leds for backlighting. I just installed them in place of the original yellow ones. I also changed the pilot leds from red to green for the buttons. I am a peculiar character.
@@MMWA-DAVE I'm suspect to talk about LEDs, as I use to replace incandescent bulbs for them... Lol
I like the idea of changing the leds but I would change them to a warm white colour to match the hue of the OEM bulbs
yep, i agree.
Hi nice video, i have w124 also, the bulb in the fan knob not light up, i tried to open the knob but it was hard to open. Is it mine cannot be open? The air distribution knob(right) is easy to open. Btw what watt is your led in the console? Many thanksss
Abdul Azim Abdul Salam the fan speed knob bulb holder turns with the knob so its not unusual for the wires to break internally eventually. It is possible to repair this. I have done it before, just not videod it. Not sure what you mean about leds
@@MMWA-DAVE so how i gonna change the bulb? How do you repair it? For the LED, what wattage of the led you put into it?
Abdul Azim Abdul Salam remind me at the end of the week and i can open the switch and have a look. I only work on the cars in weekends.
@@MMWA-DAVE i see, it's okay, i already managed to pull out the knob using pliers. Finally i replaced the bulb with led
Man i literally love you!!!
Hello. I have a problem with this system. I have a Mercedes-Benz 2.5 D Wagon. Frame position in the video 1:18.
When the key is in position between 0 and 1. The car's engine shuts off normally. But when the fan switch is in position 0. The engine is very difficult, or can not turn off.
Do you have any idea what the problem is, and what needs to be replaced or repaired?
Thanks in advance.
Do you perhaps know what the bulb code is for those LEDs? Before my interior was taken apart, the left side switch light was dead and I could never find any replacement bulbs mainly because no one knew the bulb code/number.
likewise- taking the dash apart enough to get at a bulb isn't that tricky, but its fiddly enough to only want to do it once haha
@@mattteee2973 exactly. Especially since most of the parts are old, break easily and are extremely hard to find.
They are just t5 wedges, incandescent versions come in different wattages depending on application, using the wrong one results in melted plastic. Using LED’s solves this concern and they last basically forever. As with just about everything else i buy, they came fron eBAy.
W124 sundrof feet how to wear the video will come because I don't know how to wear it?
Have you come across any issues with the vent controls? The other control knob next to the fan speed control ?
cant say that i have, has yours jammed up?
@@MMWA-DAVE yes does not turn to all 4 settings.. just .. just not sure if it’s a switch issue or if it is more sinister that that as it seems like it has a mechanical connection .. and is not an electrical switch.. 🤷♂️
@@seang2822 It can either be the switch mechanism or one of the flaps inside the airbox has jammed. Not a nice situation to be faced with. I would swap in another switch mechanism first as it’s easiest. Airbox repairs are a complete nightmare.
@@MMWA-DAVE thanks.. I heard the whole ac/ climate control system can be very expensive to fix in these cars .. and am dragging my feet to delay opening a potential can of worms 🤦
Hello. The middle bulb of the right knob does not light up, everything else lights up, the bulb itself is not broken, where is the problem? I hope you can help me.
its probably the thin wires that come up the centre of the shaft, they break away from the soldered connections.
@@MMWA-DAVE And what can I do to make the light come on again?
Hi, i have a AC dilema, i need to know what Part Number is written on that ac control panel, i cannot seem to find a good wiring schematic for this type of AC, i mean heater core has only 2 way switch over valve, not 4, not 7... and if i put DTC tester on car, i get 58 blinks witch means that valve block (4 connections) Y11, short-circuit or open. Can you help me please with that part number, or a wiring diagram that matches your AC system please? Thanks !
as far as im aware - no electronic version of the wiring diagram exists for this type (tempmatik) I have never had one. I’ve only ever seen it in the paper w124 service manuals. (which i also don’t have) The Australian version service manuals have it, the USA version manuals which as usual are all over the internet, do not. Part number of my panel I can give later, I have several spares.
@@MMWA-DAVE thank you very much, i think that part number will help me figure it out 👌
@@MMWA-DAVE i was looking at older videos, and find a part number here, ua-cam.com/video/PUbubrg8or0/v-deo.html , can you please confirm that this is the ac panel of the car with only 2 way switchover block ( i mean the car in this clip )? 1147328524 bosch and 124 830 19 85 mercedes PN. Thanks again. I have some AC wiring if you want them, i can give it by mail. Have a nice day :)
@@drideanugabriel2098 all Australian version w124’s have duovalves. Later have the later version with integrated pumps. Be aware though, there is an even earlier version control panel if your car is a very early version. The electrical socket on the rear is different and physically will not plug into this version harness
@@MMWA-DAVE Yes yes, i know that they have duo valves, but i was talking about the switchover valve block, that actuates the vacuum pods from heater box, here take a look at your video ( ua-cam.com/video/MelDNbPAdEA/v-deo.html ) min 4:11 you will see the switchover valve block that i was talking about, so to clarify the situation, i think my car has a newer AC panel, why? because if i scan it will give me that 58 blinks error, i see that you car has same heater box system as mine does, and i think that your ac panel is correct for my car also. Later models came with diffrent switchover valve blocks, some came with a 4 way valve block ( noted as Y11 in wiring diagram ) and later one came with 7 way valve block ( noted as y7 in wiring diagram ), i think my system and yours is something inbetween those changes, there is also a earlyer system noted with y13, our system works with Y13/1 switchover valve. So if you put a newer ac panel in your system, if you test it with diagnostic tool, it will give you some weird errors that shouldn't be there, I know i'm not explaining very well, i'm sorry. I hope you understood something :)
My 300ce has always hissed if I don't leave the knob set between off and pos.1, will have to change the switch now I've seen it.
I still don't quite understand why an electrical fan speed switch has a vacuum connection though?!?
Matt Teee its not the switch - the hiss is because the vacuum pods have failed. The reason for the vacuum connection is so outside air is sealed off in position 0 and fresh air is allowed in with switch between 0 and 1. As you can see from the video they are not easy to access with the dash installed. I wont be changing them on the blue/black 124.
frozen hands? just turn the temp up a little.
so helpfull video. big thanks 👌🏻👍🏻
Do you have any idea of how to work the fan control switch so it turns on & off with the ignition key. If I lock the car after turning off the ignition & leave the fan on a low setting, I can come back to a flat battery, which has happened. If you can come back with a way to control the fan switch with the ignition, I would be most appreciative........to anyone!
the fan should only operate in key position 2, you have an electrical issue if it is operating without the key. Unless you have remnants of the optional independent fuel burning heater malfunctioning. That option was available in cold countries.
@@MMWA-DAVE Yes, I know the fan should only work in the accessory ON position but it has been hard wired into the No.10 fuse....heatable rear window....& when you take the fuse out, the fan blower does not work, along with the heatable rear window. This fuse is obviously not controlled by the ignition key curcuit.What fuse is it wired into & on a second issue, how do you pull the two knobs off the update model to gain access to the hazard warning switch which is U/S in my car? Mine won't pull straight off & as you said, no screws on either side of the radio either. Thanks, Rick.
@@nickhighman4455 I think I know what's going on here. On the later models there was an issue with the fusebox melting specifically at the blower motor fuse. I suspect someone has done a very imperfect repair and tapped into another circuit. The correct factory approved repair method was to disuse the original fusebox location and hard wire in an external fuse holder. It is supposed to sit outside the box. If it was my car I would be opening up the fuse box and trying to establish what the hell has been done, finding the correct external fuse modification from a wreck or wiring in an alternative external fuse. If your car has the manual 2 zone system like mine with the knobs they simply pull off. Under them it is very self explanatory with big nuts that need to be removed on the knob shafts themselves. The shafts then click out sideways. The late cars as you say wont have the screws near the radio so the wood will just pivot upwards once the knob shafts are free then you have access to the hazard switch. I am unfamiliar with the automatic push button system if that is what you have.
@@nickhighman4455 In answer to your question also, on my car the blower motor has its own fuse - fuse 12. So some investigation is required under the fuse box to see whats happened / been done.
@@MMWA-DAVE Absolutely right. I've just talked to my son who confirmed the original owner of the car here in Toowoomba, had issues with the blower motor fuse melting & had the Green/Black wire from the blower motor hard wired into the underside of the fuse box at position No.10 (a fuse that's for the rear window demister & controlled independently of the ignition switch) I've pulled the fuse box apart & there at No.10 is the elusive wire, that, when wired directly across to the battery, runs the blower motor. Now I just have to pick up a power wire from the accessory side of the ignition switch & problem solved. The external fuse is a damn good idea. Thanks for all your help with this matter, now for the next big issue........getting those two knobs off the air con. rotary switches so i can get at the hazard switch. At the moment, they just won't come away. And yes, mine also has the manual 2 zone system but they just won't budge. Much appreciated for you help in this matter!
Hi..i had issue similiar like this, it start at speed 3 but if 1 drop it to speed 2 or 1 it will off and then i can hear sound inside the console like "krak krak krak" like ac fan wheel but i dont know
Do you know what it is?sorry to bother you and for my bad english..thank you sir
Blower bearing. Must change ac blower. Google w124 ac blower.
what bulbs are these white ?
these are just t5 LED bulbs
Hello,
I have an issue with my 300e 24, when I activate the level 3 or 4 of air fan, few time after it stops. Then I check fuse 12 of fusebox and it's completely melted...
Any idea what could be the problem?
Kind regards!
Dj Campos Chinese plastic fuses are rubbish. Purchase ceramic ones with brass/copper fuse materials. They are available online from Europe. If the fuse is still blowing at these speeds the motor itself may be starting to seize or the fuse holder is the issue. But absolutely do not use cheap plastic fuses.
@@MMWA-DAVE When I bought the car (2 years ago) all air levels (1 to 4) were working correctly and fuse 12 didn't weld...So I think I have an issue, one friend told me maybe was the potentiometer of the level selector.
But I think the problem is maybe that current (A) it's too high (maybe air fan it's skimming with something and that's why it has overconsumption).
I don't know how to diagnose this .. 🤔
Dj Campos this is another job for a multi-meter - if the one you have can measure amps that high. Most likely not though. The fan motor bearings do seize with age and if the motor is getting tight to turn it absolutely will draw excessive current. The fan switch has nothing but contacts in it. Its just switching between coil resistors up on the firewall under the windscreen in a metal cage. Position 4 straight battery voltage is going to the fan and position 3 the lowest amount of resistance. I only ever operate my fan at position 1 or 2 if the airconditioner is working well you dont really need the upper speeds and Western Australia is as hot as hell in summer.
@@MMWA-DAVE Well I also would like to use air conditioner but it doesn't work too ☹️. Last year I paid 330€ to mechanic and he did nothing. Air conditioner still not working... And it can be because of lot of things so...
Dj Campos with the age of these cars the ac system almost certainly needs to be completely rebuilt- this is cost prohibitive to pay someone to do so i did it myself. My blue black car’s ac has worked perfectly with no leaks for 5 years now. I will also be doing the same on the red project when the engine is back in and running I already have all the parts
When you hold at 2:39 you can see the main 3 buttons for the AC, starting by lowest button which is the air being recycled or not, the middle one is the AC button itself and then the one that comes in first place, does anybody know what that button for? I need to know what is it please
mohammed jamal top button runs the compressor regardless of the interior temperature. Its for defogging the front window. I use it all the time to keep the airconditioner lubricated in winter time.