Fault Conditions

A/C Relay Coil Circuit. Short to B+.







Fault symptoms
- A/C malfunctioning.

On-Board Diagnostics
Type of diagnosis:
- Continuous. But interrupted when fault criteria fulfilled and will not restant until next driving cycle.

Enable criteria:
- Ignition in ON position. A/C request has previously arrived on the bus on some occasion (cars with A/C). Output active.Fault criteria:
- Output voltage exceeding 2V for more than 1 s.

Dependents:
- None.

System reaction to a fault:
- Air mass control A/C compensation blocked.

OK report:
- Enable criteria fulfilled. A/C (Bus from DICE) is ON and fault criteria not fulfilled within 1.5 s.

Fault handling: Fault Handling III, Other Emission-Related Component & Function
- Type III. CHECK ENGINE does not go on.

Diagnostic help
Fault diagnosis concerns electrical fault in connecting leads or in the relay.
Functions in the diagnostic tool related to the fault:
- Activate A/C relay output.

For more information, Tech 2 Menu Structure, DTC Menu, Read Value, Activate, Sys Info

Checking the wiring
Jiggle the wiring harness at several points and in different directions to detect intermittent breaks and short circuits. Observe the multimeter, diagnostic tool or test lamp during the check.

Proceed to Diagnostic Procedures Checking the Relay Power Supply