What does it mean?
This is a generic diagnostic trouble code (DTC) applicable to most vehicles from 1996. Specific repair steps may vary by make/model.
The fans used to cool engine radiators are powered by electric motors. These motors are turned on and off by the Powertrain Control Module (PCM) based on readings from the Engine Coolant Temperature (ECT) sensor. In other words, when the ECT reaches a predetermined temperature, the PCM turns on the fans. Then, when the ECT cools to a predetermined temperature, the PCM turns off the fans.
The PCM controls the cooling fans by sending a ground signal to the cooling fan relay. The voltage on the signal circuit is high, around battery voltage, when not commanded (not grounded). The opposite is true when commanded on (grounded), the voltage is somewhere near zero. DTC P0692 is set when the PCM detects that the voltage remains high when the cooling fans are activated.
Symptoms
and code severity
Symptoms of a P0692 code may include:
- Engine overheating
- Check engine light illuminated
The possibility of engine overheating due to inoperative cooling fans is very likely, so caution is advised if driving the vehicle when conditions for setting this DTC are present. It should be repaired as soon as possible.
Possible causes for setting this code are:
- Faulty cooling fan relay
- Blown cooling fan fuse
- Faulty PCM (rarely)
Diagnostic and Repair Procedures
Based on my experience, a faulty cooling fan relay is the most common cause of this DTC. A simple way to check the relay is to locate it and visually inspect other relays identical to it, then swap the two relays. Clear the codes and operate the vehicle. If the code does not return, replace the relay. If it returns, suspect a possible PCM issue.
Note: Absolutely ensure the relay you are swapping is identical in every way. Installing an incorrect relay could damage the PCM. Nissan in particular has relays that appear the same in color and plug into the same socket but are different and will damage the PCM.