Need Help on 300e - PeachParts Mercedes-Benz Forum

bigbenzman · #1 05-02-2003, 10:34 PM

I am having a problem with my 1990 300e and I can't determine the cause. After driving the car for a few minutes, the red light on the Recirculation Switch will begin flashing, once this happens, the air from the vents is hot, and the engine starts running rough, and sometimes even quits. Most of the time, I can cut the engine off and restart, and the light quits flashing, but the same thing happens after driving again for a few minutes. The Climate Control doesn't seem to effect this problem as it will happen when the A/C or even the heat is on. I have already replaced the Voltage Regulator, Overvoltage Relay, and several other items. Can anyone help with this?

Bigbenzman

chowpit · #2 05-03-2003, 12:38 AM

Does this ever happen when the heat or A/C is not on? AND when it does happen does the system go to full defrost? If it goes to full defrost then you are experiencing a complete vacuum failure in you climate control system. Carefully inspect all vacuum supply lines, check valves and hoses.
HTH

bigbenzman · #3 05-03-2003, 10:23 AM

Hi Scott,
Thanks for the response. I have experienced this problem even when the Climate Control system is turned off. It does not appear to go to full defrost, as the air is not blowing very hard, but the air coming through the vents is hot.

Ken

bigbenzman · #4 05-04-2003, 11:58 PM

Any other thoughts?

Bigbenzman

stevebfl · #5 05-06-2003, 08:09 AM

Hard to judge where to start here, but I always start with an identifiable symptom.

I would probably rather figure out why it didn't run right first. one must identify what is different when the event occurs.

From the A/C side of it. Check the fault codes at pin #7 using the impulse technique. Do not turn the car off before doing this as the codes only will be present during the event.

My feeling is that you have some sort of power distribution problem. check your fuses for voltage drop during the event, particularly fuse 5.

#6 05-06-2003, 12:46 PM

Hello,

have a look on your distribution rotor and cap.

Mine was totally stuck (engine ran for few minutes and then dies).

Changed them ----> no more problems

Good luck

bigbenzman · #7 05-08-2003, 12:26 AM

Thanks for the info. Steve, you mentioned checking for fault codes on pin number 7. I did not have a impulse code reader, so I made one tonight based on comments and a wiring diagram from members on this site. The code reader I made has three wires coming out of it, one was marked as a positive, another marked as negative,(I assume these wires should just be hooked up to the battery, and then the third wire, I suppose, is to be plugged into pin number 7. Please let me know if this is incorrect, as I am planning to try this tommorrow night. Thanks again for the assistance, I'll keep you posted on what I find.

Bigbenzman

bigbenzman · #8 05-08-2003, 11:42 PM

I checked the codes tonight, and the only code I received was a 1(one blink). I also checked the fuses, all(except those such as the lights, which were not turned on) show 12.3 volts. All this was preformed while the car's recirculation switch was blinking, and after the A/C had quit working. Any other thoughts?

Bigbenzman

bigbenzman · #9 05-11-2003, 09:35 PM

Does anyone have any suggestions?

bigbenzman · #10 05-19-2003, 01:36 PM

Does anyone have any thoughts on this? I really need someone to point me in the right direction on this. Thanks in advance for any assistance you can offer.

Bigbenzman

#11 05-19-2003, 11:25 PM

HEY MAN, UNPLUG THE CLIMATE CONTROL COMPLETELY, IF THE ENGINE RUNS OK FOR SOME TIME, REPLACE THE CLIMATE CONTROL UNIT.

SHEM