Test Point 30 - Ground Connection/Plug Connections (V)

TEST POINT 30 - Ground connection/plug connections (V)

Ground connections
^ Ground lead (2x) from wiring harness to engine block.
^ Battery ground lead at clutch bell housing (engine ground) and body (body ground, next to battery).
^ Fuel pump ground between rear lock crosswall and spare wheel well.
^ Are ground connections tight and free from corrosion?

If not, undo, clean and retighten ground connections as specified.

CAUTION: Never start the engine as long as the ground lead between body and engine is disconnected! This will destroy the control unit immediately.

Plug connections
Are all plugs connected correctly, not loose and not corroded? The pins and sleeves of the plugs must not be bent!

^ The 55-pin plug on the Digital Motor Electronics (DME) control unit (behind the floor plate in the passenger footwell)
^ A 14-pin plug in the engine component next to the brake booster
^ A 3-pin plug for reference mark/engine speed sensor and a 3-pin plug for the oxygen sensor behind intake pipe for cylinder no. 4 (remove cover at fuel ring pipe first)
^ A 3-pin plug at throttle potentiometer
^ A 2-pin plug at tank ventilation solenoid valve (at the brake booster)
^ A 6-pin plug at the air mass sensor
^ A 2-pin plug at NTC II (The temperature sensor is screwed into the engine block above the left-hand balance shaft near cylinder no. 1)
^ A 3-pin Hall sender plug (behind the camshaft drive gear)
^ A 2-pin plug for knock sensor I (between intake pipe for cylinder no. 1 and 2)
^ A 2-pin plug for knock sensor (between intake pipe for cylinder 3 and 4)
^ A 3-pin plug for the idle stabilizer
^ One 2-pin plug for each of the 4 injection valves

The 968 is fined with a standard control unit. The control unit is coded accordingly depending on the vehicle model. The type of coding may be retrieved under the Version coding heading in the Actual values menu. Power to the DME control unit is supplied across ignition lock terminal 15 and terminal 30.