Hi
I'm wondering about how much the PCM can be modified when flashing. I've read that codes for the fan can be removed so that a regular fan can be installed but I've got a slightly more complicated scenario.
When I tow, I get P0495 codes, Fan exceeded 1600RPM for 81 seconds. It only happens if the engine RPM has been over 1800RPM for 120 seconds and the PCM commands 0 percent duty cycle from the cooling fan. I get these when I go up a steep grade in 2nd or first towing the trailer, the engine revs high and the fan spins too fast and by the time I've reached the top I've got a CEL.
The P0495 code doesn't invoke limp mode or affect power/efficiency of the vehicle but it does mean that I wouldn't notice if there was a second code because the CEL is already lit.
@Limquat - can the parameters be changed? Could the 1800RPM be changed to 2400RPM or could the 81 seconds be changed to 300 seconds? I don't know how far you can go when you reprogram, is it this granular or is it just an ability to disable the code from turning on the CEL?
JayArr
I'm wondering about how much the PCM can be modified when flashing. I've read that codes for the fan can be removed so that a regular fan can be installed but I've got a slightly more complicated scenario.
When I tow, I get P0495 codes, Fan exceeded 1600RPM for 81 seconds. It only happens if the engine RPM has been over 1800RPM for 120 seconds and the PCM commands 0 percent duty cycle from the cooling fan. I get these when I go up a steep grade in 2nd or first towing the trailer, the engine revs high and the fan spins too fast and by the time I've reached the top I've got a CEL.
The P0495 code doesn't invoke limp mode or affect power/efficiency of the vehicle but it does mean that I wouldn't notice if there was a second code because the CEL is already lit.
@Limquat - can the parameters be changed? Could the 1800RPM be changed to 2400RPM or could the 81 seconds be changed to 300 seconds? I don't know how far you can go when you reprogram, is it this granular or is it just an ability to disable the code from turning on the CEL?
JayArr