2005 c230 compressor p0128 code
01-25-2012, 03:59 PM
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2005 c230 kompressor
2005 c230 compressor p0128 code
The facts:
Any reference to OBD means a generic elm327 scanner and touchscan software.
About 3 months ago the CEL came on and OBDII reported several error codes mostly associated with the MAF. After a little research I found there was a factory recall for oil fouling a wiring harness. After a day at the dealer the MAF, a few other components, and all of the error codes, save one, were corrected at the expense of MBUSA.
The lone remaining DTC was P0128. The service tech said it was probably the thermostat stuck open and wasn't covered.
Under city driving conditions OBDII reported coolant temps of in the range of 79C to 81C. Under harder conditions (uphill grade, 70mph) the reported coolant temp got to 83C.
The dash gauge appeared to report a few degrees higher although its a little difficult to tell.
Replaced the thermostat. All operating conditions were identical to the old thermostat.
Replaced the sensor. All operating conditions were identical to the old sensor.
The cooling fan does not appear to come on under normal conditions.
After warm up the coolant in the reservoir appears to be 5C to 8C above the OBDII reported temp using a digital temp sensor probe (I haven't calibrated the probe except @ 0C).
The only time OBDII reports 90+C is when the vehicle is operated with the reservoir cap removed. Then temps increase to near 100C.
The vehicle needs to be smogged but will never make it with the P0128 hanging around.
Any suggestions?
Any reference to OBD means a generic elm327 scanner and touchscan software.
About 3 months ago the CEL came on and OBDII reported several error codes mostly associated with the MAF. After a little research I found there was a factory recall for oil fouling a wiring harness. After a day at the dealer the MAF, a few other components, and all of the error codes, save one, were corrected at the expense of MBUSA.
The lone remaining DTC was P0128. The service tech said it was probably the thermostat stuck open and wasn't covered.
Under city driving conditions OBDII reported coolant temps of in the range of 79C to 81C. Under harder conditions (uphill grade, 70mph) the reported coolant temp got to 83C.
The dash gauge appeared to report a few degrees higher although its a little difficult to tell.
Replaced the thermostat. All operating conditions were identical to the old thermostat.
Replaced the sensor. All operating conditions were identical to the old sensor.
The cooling fan does not appear to come on under normal conditions.
After warm up the coolant in the reservoir appears to be 5C to 8C above the OBDII reported temp using a digital temp sensor probe (I haven't calibrated the probe except @ 0C).
The only time OBDII reports 90+C is when the vehicle is operated with the reservoir cap removed. Then temps increase to near 100C.
The vehicle needs to be smogged but will never make it with the P0128 hanging around.
Any suggestions?
Last edited by 3chordpete; 01-26-2012 at 10:37 AM. Reason: Follow-up
