PowertrainP0646

Serious

Severity: Serious - have it checked soon

A/C Clutch Relay Control Circuit Low

35 brands affected · Generic SAE J2012 description.

Key terms: Control module: a small computer that runs one part of the car · SAE J2012: the standard generic code list · Powertrain: engine, transmission and emissions

1What it means in plain English

The engine computer or one of its output circuits has a fault.

2Common causes

Engine control module fault
Power or ground connection problem
Low battery or charging voltage
Wiring short or open circuit
Software or memory fault

3Can I drive?

Serious · drive with care

If the engine runs normally, drive carefully to a workshop for diagnosis. If it runs badly, stalls, or will not restart, have the car towed.

This page gives general information. It is not professional advice. For a definite diagnosis and a repair quote, ask a qualified mechanic to inspect the car.

4Brand data 35

Brand	Code	Description	System
Ashok Leyland CV	P0646	Driver assist & Steering Brand	Powertrain
BAIC Motor	P0646	A/C Clutch Relay Control Circuit Low Brand	Powertrain
Mercedes-Benz	P0646	A/C Clutch Relay Control Circuit Low SAE	Powertrain
BMW	P0646	A/C Clutch Relay Control Circuit Low Brand	Powertrain
BYD	P0646	A/C allowed control circuit low Brand	Powertrain
Chery	P0646	A/C Clutch Relay Control Circuit Low Brand	Powertrain
Daewoo	P0646	A/C Relay Voltage Low Brand	Powertrain
DFFS	P0646	A/C Clutch Relay Control Circuit Low Brand	Powertrain
DFFX	P0646	A/C Clutch Relay Control Circuit Low Brand	Powertrain
DFXK	P0646	A/C clutch low voltage short Brand	Powertrain
EOBD	P0646	Styrekrets for A/C-clutchrelé lav Brand	Powertrain
Geely	P0646	A/C Clutch Relay Control Circuit Low Brand	Powertrain
GM	P0646	A/C Clutch Relay Control Circuit Low Brand	Powertrain
Great Wall	P0646	A/C compressor short to ground Brand	Powertrain
Hafei	P0646	A/C Clutch Relay Control Circuit Low Brand	Powertrain
Holden	P0646	Air Conditioning (A/C) Compressor Clutch Relay Control Circuit Low Voltage Brand	Powertrain
Honda	P0646	A/C Clutch Relay Control Circuit Low SAE	Powertrain
Hyundai	P0646	A/C Clutch Relay Control Circuit Low SAE	Powertrain
Isuzu	P0646	A/C Clutch Relay Control Circuit Low SAE	Powertrain
Land Rover	P0646	A/C Clutch Relay Control Circuit Low SAE	Powertrain
Maserati	P0646	Air Conditioning Control Circuit Low Brand	Powertrain
Mitsubishi	P0646	A/C power supply relay low Brand	Powertrain
Opel	P0646	A/C Clutch Relay Control Circuit Low Brand	Powertrain
Peugeot	P0646	A/C Clutch Relay Control Circuit Low SAE	Powertrain
Porsche	P0646	Relais Klimaanlage - min Brand	Powertrain
Proton	P0646	A/C power supply relay low Brand	Powertrain
Saab	P0646	A/C Clutch Relay Control Circuit Low Brand	Powertrain
MG (SAIC)	P0646	A/C Clutch Relay Control Low Brand	Powertrain
Sprinter	P0646	A/C Clutch Relay Control Circuit Low SAE	Powertrain
SsangYong	P0646	Air conditioner compressor relay circuit short to ground Brand	Powertrain
Suzuki	P0646	A/C Clutch Relay Control Circuit Low Brand	Powertrain
SWM Motor	P0646	Air conditioner relay short circuit to low voltage Brand	Powertrain
Tata	P0646	A/C Clutch Relay Short To Ground Brand	Powertrain
Toyota	P0646	A/C clutch relay short to low voltage or open circuit Brand	Powertrain
Volkswagen	P0646	AC Clutch Relay Control Circuit Low Brand	Powertrain

Legend: SAE is the generic J2012 description; Brand is text taken from that manufacturer’s data. Manufacturer rows keep the wording and language of the source data, and non-English text is tagged so screen readers pronounce it correctly.

5Extended variant codes 1

These 7-character codes are manufacturer-specific variants of P0646 and may be reported by some scan tools.

Brand	Code	Description	System
Hyundai	P064600	is set when '0A' is detected in Aircon relay control circuit for more than 1 sec. This code is due to open or short to ground in Aircon relay control circuit or internal open in relay component Brand	Powertrain

6Related codes

Browse Pxxx codes or P064xx codes.