T8 / P0646 00
Read the instructions below then
start the fault diagnostic procedure.
Symptom: A/C not working, no cooling.
Compressor may run continuously.
Coolant may have been drained from the AC system via the safety valve when the compressor has been in continuous operation.
A/C Relay Circuit. Open / Short to Ground.
Fault symptom
A/C not working, no cooling.
Compressor may run continuously.
Coolant may have been drained from the AC system via the safety valve when the compressor has been in continuous operation.
On-board diagnosis
Type of diagnosis:
Enable criteria:
| Battery voltage must be between 11 - 16 V. |
| Ignition ON or Engine running. |
Fault criteria:
| When voltage on the output is below 2.0 V for more than 1 s. |
Dependent:
System reaction to a fault:
| Output to the A/C relay is switched off. |
OK report:
| Fault criteria NOT fulfilled for 2 s. |
Fault handling:
| Type III without Check Engine. |
| (See section Fault handling III, "Other emission-related components and functions" for more information.) |
Checking the wiring harness
Move the wiring harness at several spots and in several directions to reveal intermittent breaks and short-circuits. Check switches, connectors and crimp connections for oxidation, retracted pins and pin clamping force.
Diagnostic help
Diagnosis regards:
| Electrical fault in connecting leads or component. |
Functions in the diagnostic tool related to the fault:
| (See also description of readings/activations in diagnostic tool) |
