U3504

Control Module Input Power B Circuit Range/Performance

Severity

⚠️ Medium

Can you drive?

Yes, but get it checked soon

Approx. repair cost

$17–89 (est.)

Symptoms

Unstable operation of comfort systems (for example, electric windows, central locking)
Check Engine light comes on
The control module may periodically shut down
Errors in other systems associated with this module

Causes

Poor contact in module connectors
Blown power fuse
Open or short circuit in wiring harness
Power relay fault
Problems with the control module itself

How to Fix

Check and replace power supply fuses
Inspect and clean the module connector contacts
Check the integrity of the wiring harness
Check the voltage at the module terminals
If necessary, replace the control module

Related codes

U3503 U3505 U3506