P0653

Symptoms

• Check Engine light comes on
• Several sensor codes with inflated values
• Engine emergency mode
• Incorrect mixture formation (rich mixture)
• Possible damage to sensors due to overvoltage

Causes

• Short circuit of reference voltage wire B to power wire (12 V)
• ECU reference voltage regulator internal fault
• Wiring harness insulation damage
• Incorrect connection after repair
• Faulty sensor with a short to positive (rare)

How to Fix

1. Check voltage at circuit B sensor reference pins
2. Check voltage reference wire B for short to power.
3. Inspect the wiring harness for insulation damage
4. Disconnect the sensors one at a time and check the voltage change
5. If the external wiring is in good working order - diagnostics of the ECU on the bench
6. If necessary, repair or replace the ECU

Related codes

Error P0653 by Vehicle Brand