P0480

DTC P0480, P0481 or P0691 (2.0L)

Circuit Description
The powertrain control module (PCM) controls the low speed cooling fan operation by grounding the cool fan 1 relay control circuit with an internal solid state device called a driver. For high speed cooling fan operation, the PCM grounds the cool fan 2 and S/P relay control circuit at the same time the cool fan 1 control circuit is grounded. Battery positive voltage is supplied to the cool fan 1, cool fan 2 and S/P fan relays. When the PCM is commanding a fan relay ON, the voltage of the control circuit should be low, near 0 volts. When the PCM is commanding a fan relay OFF, the voltage potential of the control circuit should be high, near battery voltage. If the fault detection circuit senses a voltage other than what is expected, the DTC will set.

If the PCM detects an improper voltage level on the cool fan 1 or cool fan 2 speed driver circuits, then code P0480, P0481 or P0691 will set and the effected driver will be disabled.

DTC Descriptors
This diagnostic procedure supports these DTCs:
^ P0480 is for the low speed cooling fan relay control circuit.
^ P0481 is for the high speed cooling fan relay control circuit.
^ P0691 Is for the cooling fan relay control circuit.

Conditions for Running the DTC
^ The ignition is ON.
^ System voltage is between 9 - 18 volts.
^ The relay control circuit is transitioned from OFF to ON or ON to OFF.

Conditions for Setting the DTC
^ The PCM detects an open, a short to ground, or a short to voltage on the cooling fan relay control circuit.
^ The above conditions are present for at least 30 seconds.

Action Taken When the DTC Sets
^ The PCM will illuminate the malfunction indicator lamp (MIL) during the second consecutive trip in which the diagnostic test has been run and failed.
^ The PCM will store conditions which were present when the DTC set as Freeze Frame and Failure Records data.

Conditions for Clearing the MIL/DTC
^ The PCM will turn OFF the MIL during the third consecutive trip in which the diagnostic has been run and passed.
^ The History DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
^ The DTC can be cleared by using the scan tool.

Diagnostic Aids
^ If the condition is not present, refer to Testing for Intermittent Conditions and Poor Connections.
^ Review the Freeze Frame/Failure Records vehicle mileage since the diagnostic test last failed. This may help determine how often the condition that caused the DTC to be set occurs.

Test Description








These numbers refer to the step numbers on the diagnostic table.
2. Listen for an audible click when the cool fan relay 1 operates. Command both the ON and OFF states. Repeat the commands as necessary.
3. Listen for an audible click when the S/P and cool fan 2 relays operate. Command both the ON and OFF states. Repeat the commands as necessary.