Lotus Evora - A;C Compressor Lock Sensor Circuit

Lotus Service Notes Section EMR
Page 77
A/C Compressor Lock Sensor Circuit
B1422 A/C Compressor Lock Sensor Circuit
Description:
The ECM monitors the A/C compressor speed. If this speed is lower than the engine speed the ECM will turn
off the A/C compressor clutch. This is to prevent belt damage due to slippage.
Component connections:
Connector Description ECM Pin ECM Connector
1 Lock sensor +ve C1 32 Way (Left)
2 Lock sensor -ve B1 32 Way (Left)
Monitor:
• Continuous
Enable Criteria:
• Enginerunning
Disable Criteria:
• P0646,P0647A/Ccompressorclutchfault
Malfunction Criteria:
• A/Ccompressorspeederrorgreaterthan20%
Potential failure modes:
• A/Ccompressorclutchmechanismslippingorseized
• A/Ccompressordrivebeltslipping
• Locksensorwiring
• Locksensorfailure
• ECMinputcircuitfailure
Diagnostic Mask:
• Theservicelightwillbeilluminatedfor30secondsafterenginestartifthefaulthasbeenpresentforthe
previous two trips.
2009/02