Ground Connection

PRINCIPLE OF OPERATION, GROUND
The control module's power output stage is connected to ground at grounding point G7P.
- pin 2 grounds the outputs to the ignition coil module
- pin 14 grounds the outputs to the injectors
- pin 24 grounds other actuating device outputs (idle speed control, etc.)

The control module connections are connected internally with each other and to pin 19. It will be possible to start the engine if any of these pins are connected to ground.

The mass air flow sensor and the oxygen sensor preheaters are also connected to ground at grounding point G7P.

Reference Ground
Reference ground from grounding point G7L is applied to pin 10 of the control module so that the voltage from the oxygen sensors can be measured with greater precision. The MIL (CHECK ENGINE) lamp will light up without reference ground on pin 10.

IMPORTANT: The three ground connections on the ignition coil module bracket must always be kept separate.





Sensor Ground
The following sensors are connected to ground via pin 30 of the control module:
- mass air flow sensor
- coolant temperature and intake air temperature sensors
- throttle position sensor
- knock sensors and their screened leads

Pin 19 of the control module and the following sensors are connected to ground at grounding point G7S:
- the camshaft position sensor and its screened lead
- the screened lead of the crankshaft position sensor
- the screened leads of the oxygen sensors