B0997

Auxiliary Electronic Control Unit Performance

Severity

⚠️ Medium

Can you drive?

Limited driving only, diagnose soon

Approx. repair cost

$56–222 (est.)

Symptoms

Check Engine light comes on
Reduced efficiency of connected systems
Incorrect operation of auxiliary functions (for example, climate control, airbags)

Causes

Malfunction of the auxiliary control unit
Problems with wiring harness or connections
Software errors in the control unit
Short circuit or open circuit

How to Fix

Carry out diagnostics using an OBD-II scanner to clarify the problem
Check the integrity of the wiring harness and connections
Update or reflash the control unit software
If necessary, replace the faulty control unit

Related codes

B0998 B0996 U0100