Climate Control - Pressure Sensor Invalid Diagnostic Value
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Climate Control - Pressure Sensor Invalid Diagnostic Value
I've had my W140 (1996 S320) for 6 or so years and the AC has never worked (heat and all other aspects work fine). In the past I had tried some different Climate Control head units to see if that would fix my problem, but to no avail. I've learned to live with it and just don't drive it during the summer. I recently realized via the climate control diagnostic menu, that the diagnostic value (7) for the pressure sensor was displaying a wildly invalid value (32). In the past I had assumed that it was in PSI, but then I found a post saying that it's always in bar.
Seeing as the compressor has never kicked on since I've owned the car I figured I have a bad pressure sensor and that would explain the AC not working. Sweet! I have access to all the evacuation and recharge equipment so this is beginning to look like a relatively easy fix! I ordered a new sensor (and drier).
When the new sensor arrived I decided to plug it in in place of the old one (not "installed" mind you) just to see that I get a valid readin. Nope. I get the same "32". If I leave the harness unplugged I get an "E", so it's pulling something from the sensor. I measured the plug voltage and with the engine off, I think it was 4.8v which seemed to align with what I saw online.
Now I'm concerned that going to all the trouble to replace the sensor will be for nothing. Does anyone have any ideas on some next troubleshooting steps?
Seeing as the compressor has never kicked on since I've owned the car I figured I have a bad pressure sensor and that would explain the AC not working. Sweet! I have access to all the evacuation and recharge equipment so this is beginning to look like a relatively easy fix! I ordered a new sensor (and drier).
When the new sensor arrived I decided to plug it in in place of the old one (not "installed" mind you) just to see that I get a valid readin. Nope. I get the same "32". If I leave the harness unplugged I get an "E", so it's pulling something from the sensor. I measured the plug voltage and with the engine off, I think it was 4.8v which seemed to align with what I saw online.
Now I'm concerned that going to all the trouble to replace the sensor will be for nothing. Does anyone have any ideas on some next troubleshooting steps?
