VVC Information

The S1 EU2 VVC is controlled by the Lucas MEMS 2J ECU common with the early VVC MGFs

The S2 EU3 VVC is controlled by the Lotus K4 ECU (based on the Lucas MEMS 3)

VVC Failure Modes

ECT Sensor Error Limits to 6K RPM

MAP Sensor Error limits to 6K RPM

VVC Solenoid low resistance (should be 6.6 to 8.8 Ohms)Limits to 5.5K RPM

Cam Position Sensor Limits to 5.5K RPM

Note: Connecting the battery on wrong polarity can blow the ECU VVC control circut, as can running with a low resistance solenoid. Clearly the circuit has no protection.

Lotus S2 K4 ECU VVC Connections

| K4 Pin || Wire || Function | | 06 || Blue || VVC Oil Temp Earth | | 10 || Green Orange || VVC Oil Temp Signal | | 12 || Black Yellow || VVC Decriment | | 49 || Brown Black || VVC Increment |

Lotus S2 K4 ECU VVC DTC Codes

| Code || Description | | P1336 || S2 Crankshaft Position System Variation Not Learned | | P1480 || S2 Exhaust flap relay open | | P1481 || S2 Exhaust flap short circuit | | P1490 || S2 VVC brown increment solenoid open circuit (Black Yellow) | | P1491 || S2 VVC brown increment solenoid short circuit (Black Yellow) | | P1492 || S2 VVC blue decrement solenoid open circuit (Black Brown) | | P1493 || S2 VVC blue decrement solenoid Short circuit (Black Brown) | | P1494 || S2 VVC black oil temp sensor LOW short circuit (Green Orange + Blue) | | P1495 || S2 VVC black oil temp sensor HIGH open circuit (Green Orange + Blue) |