Mercedes Benz AC Blower running non-stop

[rmt6668]

My 2001 E240 W210 Air Conditoner seem to have a mind of its own it kept running non stop. I am trying to diagnose the fault. Temporarirly I have remove the 3 pin cable connected to the AC Blower Regulator.

I am trying to locate the AC Fuse? I cannot see where it is?

Is it possible that the Relay Power Contacts are welded & Sticking? Its a 1 inch Box Plug in Cube, 5 pin relay on the engine L side?

[fireblade]

I maybe wrong but when I had my 2005 Volvo S40, same thing happens. Only to find out that it is a standard feature to cool down the engine and interior when kept under the sun. goes on and off automatically to remove some humidity. Sometimes, I am already away from the car after parking and the blower is still running. Just to hear from Viking that it is standard. Could it be the same?

[rmt6668]

No, the fault is causing the AC Blower to rum 24hrs a day...on & on

I manage to open the fuse box & I see there is a hidden half of the fuse box, the RELAYS. But which is for AC? I suspect the one on top (yellow)

[Walter]

Try checking the relay also or the thermo-sensor switch.

[rmt6668]

"Try checking the relay also or the thermo-sensor switch."

Walter,

Where is the Relay? In the fuse box, there are Relays mark A to G?

Where is the thermo-sensor swicth located?

Can you post me picture? Mine is a E240 Yr2001 W210 model

Thanks again

[Walter]

Not familiar with W210s, only W124s. Had a similar problem, turns out the thermo sensor switch was replaced before, had to return to original. Then there was a problem with the fuse, relay and the resistor.

[smooth]

i don't know if this is related. i know someone who's 2002 MB S-class' A/C just suddenly switched to heater mode after he rolled down the driver's side window. we couldn't figure out what was the problem. tried everything and walang nangyari. (ang init i-maneho kasi heater ang gumagana.) the endpoint: the car was brought to the MB casa where they "re-booted" the ECU. that might be the solution to your problem. btw, this "re-booting" costs 60K or 80K (sorry can't really remember how much). how do they re-boot? they bring in this really high tech looking aluminum attache case thing, plug in some cables into the MB, push some buttons, and voila! ayus na ang kotse (and there went the 60K). fastest way of losing 60K i've ever seen (excluding betting in casinos that is).

[theveed]

i don't know if this is related. i know someone who's 2002 MB S-class' A/C just suddenly switched to heater mode after he rolled down the driver's side window. we couldn't figure out what was the problem. tried everything and walang nangyari. (ang init i-maneho kasi heater ang gumagana.) the endpoint: the car was brought to the MB casa where they "re-booted" the ECU. that might be the solution to your problem. btw, this "re-booting" costs 60K or 80K (sorry can't really remember how much). how do they re-boot? they bring in this really high tech looking aluminum attache case thing, plug in some cables into the MB, push some buttons, and voila! ayus na ang kotse (and there went the 60K). fastest way of losing 60K i've ever seen (excluding betting in casinos that is).

Langhiyang raket yan ah.

[smooth]

Langhiyang raket yan ah.

sorry OT pero for drama lang kaya hindi ko sinama ang ilang important info. (1) gray market kasi ang benz niya so pag dinala sa casa, may mga add-on talaga (sabi pa ng casa, kasama na daw sa 60K na yun ang "warranty" kuno), and, (2) mahal talaga yung mga firmware na yun para sa diagnostic computer nila. at the time it happened, the car was barely a year old. we went kasi muna to a non-casa benz shop (re-booting would have cost probably just 5K or something) but the firmware that the non-casa shop had was not for the same model year. balita ko ilang million ang binabayad ng casa para makakuha ng modelong firmware e.

*rmt6668, sorry wala akong maidadagdag na helpful info except ingat lang sa pagbutingting diyan sa benz mo. dami niyang computer stuff na magkaka-konekta baka kung anong mahugot mo. nung nagka-problema ang sa kakilala ko, we even called MB sa germany and while they were helpful (dami din namin sinubukang tanggaling kung anu-ano) ang kinatapusan e casa pa din ang bagsak namin

[edl100]

sorry OT pero for drama lang kaya hindi ko sinama ang ilang important info. (1) gray market kasi ang benz niya so pag dinala sa casa, may mga add-on talaga (sabi pa ng casa, kasama na daw sa 60K na yun ang "warranty" kuno), and, (2) mahal talaga yung mga firmware na yun para sa diagnostic computer nila. at the time it happened, the car was barely a year old. we went kasi muna to a non-casa benz shop (re-booting would have cost probably just 5K or something) but the firmware that the non-casa shop had was not for the same model year. balita ko ilang million ang binabayad ng casa para makakuha ng modelong firmware e.

*rmt6668, sorry wala akong maidadagdag na helpful info except ingat lang sa pagbutingting diyan sa benz mo. dami niyang computer stuff na magkaka-konekta baka kung anong mahugot mo. nung nagka-problema ang sa kakilala ko, we even called MB sa germany and while they were helpful (dami din namin sinubukang tanggaling kung anu-ano) ang kinatapusan e casa pa din ang bagsak namin

Grabe.. 2002 S-Class!! Parang pinaparusahan ng CATS yung mga bumili sa gray market..
I guess pag binili yung 2002 S-class sa CATS, it would have been covered under warranty or would have been charged way less.

[rmt6668]

Thanks guys,

But I'm not filipino & can you translate for me pls

[smooth]

Grabe.. 2002 S-Class!! Parang pinaparusahan ng CATS yung mga bumili sa gray market..
I guess pag binili yung 2002 S-class sa CATS, it would have been covered under warranty or would have been charged way less.

just to clarify, the casa we went to wasn't CATS motors. at the time, if i remember correctly, there were several MB authorized service centers and we were able to canvass among them. (it might have been more expensive in cats.) and yes, i agree that if the car was purchased from cats, it would most probably have been covered under warranty.

[rmt6668]

Where is your thermo sensor swicth located?

Are you sure they can reboot the AC Control Unit?

[rmt6668]

Hi again,

I finally manage to pull the AC Control Unit off. Attached are the pics I have taken. Surprisingly with the AC Control Unit disconnected, the Blower still kept blasting away. Is it back to the Regulator or even the Thermo Sensor Switch Faulty?

Can some one pls lead me in the right direction very much appreciated.

[edl100]

Did you find the problem part already??

I also own a W210.

I think it is the blower regulator. This usually breaks down on most W210 owners. Mine already broke down.

If you only had the PUSH BUTTON controls for the aircon then we can easily see what the problem is since that control has a built in COMPUTER DIAGNOSIS that shows the fault codes.

please bring your car to R&R motors. Look for Nemecio. If you haven't heard of them, they service MB aircons with a computerized system using a LAUNCH OBDII computer to find error codes and erase them. You can easily see what component is broken than through trial in error. BTW, this shop charges reasonable. They have the cheapest computer diagnosis charge anywhere.

They are located along EDSA. Coming from Q.C., go right side POEA ortigas edsa, you will see the shop on the right just across Galleria. Just a little after the Burger machine stall.

Don't even think of going to European motors or even CATS!! for sure, mahal doon ang labor.

[edl100]

My 2001 E240 W210 Air Conditoner seem to have a mind of its own it kept running non stop. I am trying to diagnose the fault. Temporarirly I have remove the 3 pin cable connected to the AC Blower Regulator.

I am trying to locate the AC Fuse? I cannot see where it is?

Is it possible that the Relay Power Contacts are welded & Sticking? Its a 1 inch Box Plug in Cube, 5 pin relay on the engine L side?

I see you are a bit of a handyman since you pulled out all those parts from the BENZ. Great!!