Pinpoint Test KF: Fan Control Relays
WARNING: This page is about a different variant/trim than selected.
Normal Operation and Fault Conditions
Refer to the DTC Fault Trigger Conditions.
Although the PCM output circuits are called LFC, MFC, and HFC, cooling fan operation is controlled by a combination of these outputs.
DTC Fault Trigger Conditions
| DTC | Description | Fault Trigger Condition |
|---|---|---|
| PCM P028D:00 | Charge Air Cooler Cooling Fan Control Circuit Low: No Sub Type Information | Sets when the PCM detects an open circuit or a short to ground from the charge air cooler cooling fan circuit. |
| PCM P028E:00 | Charge Air Cooler Cooling Fan Control Circuit High: No Sub Type Information | Sets when the PCM detects a short to voltage from the charge air cooler cooling fan circuit. |
| PCM P0480:00 | Fan 1 Control Circuit: No Sub Type Information | Sets when the PCM detects excessive current draw from the low fan control circuit when activated; or voltage is not detected from the low fan control circuit when not activated. The PCM expects to detect vehicle power voltage coming through the low speed fan control relay coil to the low fan control circuit. When the LFC_F PID reads YES, a concern is present. A short to voltage can only be detected when the PCM is grounding the low fan control circuit. |
| PCM P0481:00 | Fan 2 Control Circuit: No Sub Type Information | Sets when the PCM detects the high fan control output is commanded on (grounded) and excessive current draw is detected from the high fan control circuit; or when the high fan control circuit is commanded off and voltage is not detected from the high fan control circuit. The PCM expects to detect vehicle power voltage through the high speed fan control relay coil to the high fan control circuit. When the HFC_F PID reads YES, a concern is present. An open circuit or short to ground can only be detected when the PCM is not grounding the high fan control circuit. A short to voltage can only be detected when the PCM is grounding the high fan control circuit. |
| PCM P0482:00 | Fan 3 Control Circuit: No Sub Type Information | Sets when the PCM detects the medium fan control output is commanded on (grounded) and excessive current draw is detected from the medium fan control circuit; or when the medium fan control circuit is commanded off and voltage is not detected from the medium fan control circuit. The PCM expects to detect vehicle power voltage through the medium speed fan control relay coil to the medium fan control circuit. When the HFC_F PID reads YES, a concern is present. An open circuit or short to ground can only be detected when the PCM is not grounding the high fan control circuit. A short to voltage can only be detected when the PCM is grounding the high fan control circuit. |
Possible Sources
- Fan control circuitry concern
- Cooling fan module
- Cooling fan clutch solenoid
- Fan control relay
- PCM (12A650)