P04D4

Exhaust Brake Input Circuit Range/Performance

Severity

⚠️ Medium

Can you drive?

Limited driving only, diagnose soon

Approx. repair cost

$56–167 (est.)

Symptoms

Reduced engine braking efficiency
Check Engine Light Illuminates
Unstable engine operation when braking

Causes

Exhaust brake sensor malfunction
Open or short circuit in wiring harness
Problems with the exhaust brake itself
Engine control unit (ECU) malfunction

How to Fix

Check the integrity of the wiring harness and connections
Check the exhaust brake sensor for damage.
Check the operation of the exhaust brake
If necessary, replace faulty components
Reset the error and check if it returns

Related codes

P04D5 P04D6 P0400