What does it mean?
P1500 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: Radiator Fan Relay 1 Circuit malfunction (fan 1) .
Symptoms
- MIL on
- Radiator fan 1 does not run, or runs continuously regardless of temperature
- Coolant temperature rises at idle and in traffic while staying normal on the highway
- A/C performance drops off whenever the vehicle stops moving
- Coolant may boil over in severe cases
- In the stuck-on failure the fan keeps running with the key off and flattens the battery
Likely causes
- Radiator fan relay 1 failed, with an open coil or burnt contacts
- Corroded, loose or heat damaged terminals in the relay socket
- Open or shorted control wire between the module and the relay coil
- Blown fuse or fusible link in the fan 1 power feed
- Fan motor 1 seized or drawing high current and burning the relay contacts
- Poor ground connection for the fan circuit
- Module output driver failure
How to fix it
- Command fan 1 on with a scan tool and check whether it responds at all
- Inspect the relay and socket for melted plastic, burnt contacts and spread terminals
- Substitute a known good identical relay from the same fuse box
- Check the fuse and measure the feed voltage at the relay
- Test the control wire for continuity to the module and for shorts to ground or power
- Measure fan motor current draw and check the integrity of its ground
- Replace the relay or fan motor and repair the wiring, then confirm normal fan operation