Ignition D Control Signal Circuit High

Common symptoms

What you'll notice

• Check the wiring and connectors related to the ignition D control signal circuit for any damage or loose connections.
• Check the ignition module or ignition coil for any malfunction or defects and replace if necessary.
• Inspect the ignition switch for any faulty contacts or connections and repair or replace as needed.
• Verify the operation of the engine control module (ECM) or powertrain control module (PCM) and update or reprogram if required.
• If all other solutions fail, consider replacing the ECM or PCM as a last resort.

Common causes

Most likely first

1. faulty ignition coil
2. damaged or worn out spark plugs
3. malfunctioning ignition control module
4. issues with the ignition switch
5. faulty engine control unit (ECU)

How to diagnose & fix

Work through it in order

1. Engine misfires or runs rough
2. Decreased fuel efficiency or poor fuel mileage
3. Trouble starting the vehicle or starting issues
4. Engine stalling or cutting out while driving
5. Loss of power or decreased acceleration