Fault code P1654 – a step-by-step guide to diagnosing and fixing it

Error code P1654 is displayed and the check engine light is on - what does this mean?

The OBD system has detected a fault in the A/C clutch control or air conditioning control. This manufacturer-specific DTC P1654 usually refers to problems with the A/C clutch or its control circuit. The exact definition may vary slightly for different manufacturers, but generally relates to the A/C control system.

What causes can this fault code have?

• Defective A/C clutch relay
• Damaged wiring to the A/C clutch
• Loose or corroded plug connections
• Defective A/C clutch
• Faulty A/C pressure sensors
• Defective A/C control unit
• Interrupted ground connections
• Overload in the A/C circuit

What symptoms occur in parallel with fault code P1654?

• Air conditioning not working: The air conditioning does not cool or does not start at all
• Irregular cooling: Intermittent function of the air conditioning system
• Unusual noises: Clicking noises or rattling when the A/C is switched on
• Increased fuel consumption: Engine operates inefficiently due to control problems
• Check engine light: Permanent or intermittent display of the warning light

How to fix the problem of error code P1654?

• The repair requires a systematic diagnosis of the A/C system and the associated control circuits.
• Check and replace the A/C clutch relay: Locate relay, test electrical continuity and replace with new original part if defective
• Check the wiring to the A/C clutch: Check all cables for breaks, short circuits or insulation faults and repair or replace damaged cables
• Clean and secure plug connections: Remove all plugs in the A/C system, clean contacts and connect firmly
• Replace A/C clutch: Check clutch for mechanical defects and replace completely if worn or blocked
• Test pressure sensors in the A/C system: Check A/C pressure sensors for correct function and replace defective sensors with new ones
• Diagnose the A/C control unit: Test control unit with professional diagnostic technology and program or replace if defective