P0646low severityPowertrain
A/C Clutch Relay Control Circuit Low
on 2008 Dodge Viper 8.4L V10 · RWD
What this code means
The PCM detected a low voltage condition in the A/C compressor clutch relay control circuit. The A/C compressor may fail to operate.
Symptoms
- A/C not cooling
- Compressor clutch inactive
- MIL illuminated
Common causes
- Short to ground in control wiring
- Faulty A/C clutch relay
- Damaged connector
- PCM internal fault
Diagnostic steps
- Retrieve trouble codes
- Inspect wiring for short to ground
- Measure control circuit voltage
- Test relay and PCM driver
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Other Powertrain codes on this vehicle
P0001
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P0002
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P0003
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P0004
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P0005
Fuel Shutoff Valve A Control Circuit/Open
P0006
Fuel Shutoff Valve A Control Circuit Low
P0007
Fuel Shutoff Valve A Control Circuit High
P0008
Engine Position System Performance - Bank 1
P0009
Engine Position System Performance - Bank 2
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1