P04D4
Exhaust Brake Input Circuit Range/Performance
Generic OBD-II
Common symptoms
What you'll notice
- Check the wiring and connections related to the exhaust brake input circuit
- Inspect the exhaust brake sensor for any damage or malfunction
- Clean or replace the exhaust brake sensor if necessary
- Verify the exhaust brake system's functionality and perform any necessary repairs or adjustments
Common causes
Most likely first
- Faulty exhaust brake sensor
- Damaged or loose wiring connections to the exhaust brake sensor
- Problem with the exhaust brake control module
- Clogged or restricted exhaust brake system
- Malfunctioning engine control module (ECM)
How to diagnose & fix
Work through it in order
- Warning light on the dashboard illuminates.
- Decreased engine power or performance.
- Difficulty shifting gears or engaging the transmission.
- Abnormal engine noises or vibrations.
- Increased fuel consumption.
Read & clear P04D4 yourself
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