Mb 400sel-93. A/C COMPRESSOR TURNED OFF AFTER RUNNING, SOMETIMES AT BEGENUNG. SENSORS READING ARE 1- 9F, 2-6F, 3-84F, 4-84F, 5-85F, 6-63F, 7-8, 8-21. later after comressorturned off 1- 5, 2-7, 3-69, 4-68, 5-64, 6-86, 7-12, 8-21. After pressing preparation for test for codes, irtdoes not show on led. Left on red, right on blue, turn on, then rest, after 20 seconds ec and c, nothing is displayed. where is located the in-car temp. ssensor?. Only sensors and result could be read it

The MB 400sel-93, A/C compressor turned off, after running for a while or some times it does not turn on when engine is on. Sensor data is obtained from the digital Climate control at dash, but trouble codes can not be seen. Sensors 1 read- 9 F, 2- 6F, 3- 84F 4- 84 F, 5- 85F, 6-63F, 7-8, 8-21, 9-62F, 16-0. After compressor turned off itself, read 1- 5F, 2-7F, 3-69F, 4-68F, 5-64F, 6-86F, 7-12, 8-21, 9-62, 16-0. I just tried to collect trouble codes follwing intructions: left to red, right to blue, ignition on, REST, after 20 seconds EC AND C AT SAME TIME," BUT NO DISPLAY:. where is located the in-car temp sensor (with aspirator blower)?

Any help, thanks

In-car temp sensor is located in the dome lamp.

ON that model the a/c pushbutton sends command signal to a computer in the computer compartment & that module(base module) turns on the compressor.

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I will try to see the base model and identify it. Do you know if the in car temp sensor is ok according to the reading that I obtained. May I acquire it trough here?.

Thanks again

What you're doing doesn't sound like the same procedure described on the bottom on page 87 here - http://www.motodok.com/Documentation/Files/MB/cs1000-mb.pdf

Most A/C issues are freon low related if it ever works at all. Remember it cant be checked uless the compressor engages and you get it to around 2k rpms. Reading should be around 35 psi at 2k rpms. At idle or off gage should be pegged.

You are right. I was looking for such information, specificly for this car. Apparently I WAS USING OTHER. I really apreciate your response. Now I have all procedures. Thanks a lot.

You're welcome. Good luck with it.

I just want to add that, AC Control panel, when temp. of front both side are set to Hot(red), ONLY ONE SIDE changed to hot, since the other one STILL cold. The Control panel still displaying sensor reading without problem, but the DTC, diagnostic trouble code are not displayed. The procedures states , "place ignition in ON -position 1, but in pos.1 the control panel does not show anything, it happen on POS. 2. See what I did and the results: SENSORS: 1-9, 2-11, 3-72F, 4-72F, 5-67F, 6-64 F, 7-13, 8-24, 9-62, 16-0. For the Fault Diagnostic. 1- Turned left selector wheel to red and right to blue.2- Ignition On- pos.2, 3- AUTO button (both) automatically appeared ( it is standard in this car), 4- within 20 seconds I pressed REST and O SIMULTANOUSLY for 2 seconds, but NOTHING IS DISPALYED on left and right display.

Thanks again. Plaese how may identify the relay. My car does not has the chard for relay, only for fuses. Under the A/C wiring diagram the only relay is the Auxiliary coolant pump control relay. tHERE IS NOT AN a/c compressor relay?. Does the Base module computer releaf the relay?

I will appreciate your assistance

Comprende, I'd want an AC year round in PR. Yes, base module replaces AC relay. You can check the base module for fault codes on pin 8 of the 38 pin connector in the engine compartment. You'll need to build the code reader.

Deaneyel.

I have an OBD2 ACTRON Scanner. I just ordered the 38 pin for OBD TO OBD2 cable connector. Does it works?. Do I need another part or tool.?. Where may I acquire it. I have the reading for the sensors. What guide sohould I use to see if the reading are ok, or are malfunctions?

Thanks again. Iowe uou some Medalla beer FROM PR.

I don't think Actron works even with a 38 pin connector, because your car is still analog. You need to build the flash code reader. I sent you a PM.