What does it mean?
This is a generic powertrain diagnostic trouble code (DTC) applicable to all vehicles newer than 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 the fans on. Then, when the ECT cools to a predetermined temperature, the PCM turns the fans off.
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 it is not commanded (not grounded). The opposite is true when commanded on (grounded); the voltage is somewhere near zero. DTC P0695 is set when the PCM detects low voltage when cooling fan 3 is off.
Symptoms
and code severity
Symptoms of a P0695 code may include:
Engine overheating
Check Engine Light illuminated
The possibility of engine overheating due to inoperative cooling fans is very high, so caution is advised if driving the vehicle when conditions for setting this DTC are present. It should be repaired as soon as possible.
Causes
Possible causes for setting this code are as follows:
Faulty cooling fan relay 3
Blown cooling fan fuse 3
Faulty PCM (rarely)
Diagnostic and Repair Procedures
In my experience, a blown cooling fan fuse is the most common cause of this DTC. Checking the fuse is as simple as locating it, pulling it out, and looking at it. You can usually tell by visual inspection whether a fuse is good or not. If the fuse is indeed blown, try replacing it with the correct fuse amperage. If the fuse blows again, the next question would be when did it blow?
If the fuse failed immediately after replacement, there is a direct short somewhere between the fuse and the relay. If it failed when the engine reached operating temperature, the most likely cause is the cooling fan motor itself. With the engine and ignition key off, carefully try to spin the fan blades by hand. They should spin freely; if not, the fan motor is seized and will need to be replaced. If the fuse is good, the problem is likely the cooling fan relay. If replacing the relay does not solve the problem, suspect a faulty PCM.
Be cautious when working around components that are not only hot but also moving.