P1135 – Ford DTC

Ford DTC P1135 – Ignition Switch Signal Missing or Improper

DTC P1135 meaning on Ford

1. DTC P1135 indicates that there is a missing or improper ignition switch signal detected in a Ford vehicle.

Ford DTC P1135 symptoms

1. Check Engine Light (CEL) illuminated on the dashboard.
2. Difficulty starting the vehicle.
3. Engine stalling or rough idling.

Ford DTC P1135 causes

1. Defective ignition switch.
2. Wiring issues in the ignition switch circuit.
3. Faulty ignition switch signal.

Ford DTC P1135 seriousness

1. If left unresolved, DTC P1135 can lead to starting issues and potential engine stalling, affecting the vehicle’s drivability.

How to diagnose DTC P1135 on Ford

1. Use a diagnostic scanner to retrieve the trouble codes and identify DTC P1135.
2. Inspect the ignition switch and its wiring for any visible damage or loose connections.
3. Test the ignition switch signal using a multimeter to check for proper voltage and continuity.

How to fix DTC P1135 on Ford

1. Replace the faulty ignition switch if it is determined to be the cause of the issue.
2. Repair any damaged wiring in the ignition switch circuit.
3. Clear the trouble codes using a diagnostic scanner after the repairs are completed.

How to erase DTC P1135 on Ford

1. Use a diagnostic scanner to access the vehicle’s onboard computer.
2. Select the option to clear the trouble codes stored in the system.
3. Follow the prompts on the scanner to confirm the deletion of DTC P1135.

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