DTC P1290 [YF (2.0L Zetec)]

id0102d0872900

DTC P1290

Cylinder head temperature sensor circuit low input

DETECTION CONDITION

• If the PCM detects the cylinder head temperature sensor voltage is below threshold while the engine running to on, the PCM determines that the cylinder head temperature sensor circuit has malfunction.

POSSIBLE CAUSE

• Cylinder head temperature sensor malfunction
• Poor connection of the cylinder head temperature sensor and/or the PCM connectors
• Short to ground in wiring harness between the cylinder head temperature sensor terminal 1 and the PCM terminal 38
• Short circuit in wiring harness between the cylinder head temperature sensor terminal 1 and the cylinder head temperature sensor terminal 2
• PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1
VERIFY FREEZE FRAME DATA HAS BEEN RECORDED
• Has FREEZE FRAME DATA been recorded?
Yes
Go to the next step.
No
Record the FREEZE FRAME DATA on the repair order, then go to the next step.
2
VERIFY RELATED REPAIR INFORMATION AVAILABILITY
• Verify related service repair information availability.
• Is any related repair information available?
Yes
Perform repair or diagnosis according to the available repair information.
• If the vehicle is not repaired, go to the next step.
No
Go to the next step.
3
INSPECT CYLINDER HEAD TEMPERATURE SENSOR CONNECTOR
• Turn the ignition switch off.
• Verify that the cylinder head temperature sensor connector is connected securely.
• Is connector normal?
Yes
Go to the next step.
No
Connect the connector securely, then go to Step 8.
4
INSPECT POOR CONNECTION OF CYLINDER HEAD TEMPERATURE SENSOR CONNECTOR
• Disconnect the cylinder head temperature sensor connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Is there any malfunction?
Yes
Repair or replace the terminal, then go to Step 8.
No
Go to the next step.
5
INSPECT CYLINDER HEAD TEMPERATURE SENSOR
• Perform cylinder head temperature sensor inspection.
• Is cylinder head temperature sensor normal?
Yes
Go to the next step.
No
Replace the TP sensor, then go to Step 8.
6
VERIFY CYLINDER HEAD TEMPERATURE SIGNAL CIRCUIT FOR SHORT TO GROUND
• Inspect for continuity between cylinder head temperature sensor terminal 1 (harness-side) and body ground.
• Is there continuity?
Yes
Repair or replace the wiring harness, then go to Step 8.
No
Go to the next step.
7
VERIFY CYLINDER HEAD TEMPERATURE SIGNAL CIRCUIT FOR SHORT CIRCUIT
• Inspect for continuity between cylinder head temperature sensor terminal 1 (harness-side) and cylinder head temperature sensor terminal 2 (harness-side).
• Is there continuity?
Yes
Repair or replace the wiring harness, then go to the next step.
No
Go to the next step.
8
VERIFY TROUBLESHOOTING OF DTC P0122 COMPLETED
• Make sure to reconnect all disconnected connectors.
• Clear the DTC from the PCM memory using the WDS or equivalent.
• Start the engine.
• Is the same DTC present?
Yes
Replace the PCM, then go to the next step.
No
Go to the next step.
9
VERIFY AFTER REPAIR PROCEDURE
• Perform the "After Repair Procedure".
• Are any DTC present?
Yes
Go to the applicable DTC troubleshooting.
No
Troubleshooting completed.