Test Point 13 - Ground Connections/Plug Connections

TEST POINT 13: - Ground connections/Plug connections

GROUND CONNECTIONS
^ Engine ground, between engine and right side of body under engine.
^ Ground for ignition output stages above the right ignition coil.
^ Ground for control units under the fuel pressure regulator and the fuel pressure vaporizer.

Are the ground connections tight and free from corrosion?

- Loosen the ground points, clean them and tighten.them again as specified.

CAUTION: Never start the engine when the body-engine ground lead is not connected. This will destroy the control unit immediately.

PLUG CONNECTIONS
Are all plug connections correctly wired up and not loose or corroded? Separate the plug connections. Neither the pins nor the sleeves of the plug connections must be bent or corroded.

^ At the central electrics, the relays for the fuel pump, EZK and LH and plug W.
^ At the EZK and LH control units, the 35-pin plug in each case.
^ Plug connection for activating the ignition output stages (green/white lead). Above the central electrics.
^ At the air mass sensor, a 6-pin plug (only 5 contacts are occupied in the plug housing).
^ At temperature sensor II, a 2-pin plug.
^ At the engine speed reference mark sensor, a 3-pin plug (behind the air mass sensor).
^ At each of the 8 injector valves a 2-pin plug (first remove the ring pipe cover).
^ Knock sensor plug connections. Front sensor: plug connection at the front left, below the fuel ring pipe.
^ Rear sensor: plug connection above the right fuel ring pipe at the rear.
^ Hall sensor plug connection. Behind the housing for the camshaft drive gear, cylinder bank 1 - 4.
^ Plug connection for solenoid valve to operate resonance flap (at toothed belt cover for cylinder bank 5 - 8).
^ Plug connection, fuel tank venting solenoid (at toothed belt cover for cylinder bank 1 - 4, below the water hose).
^ Plug connections for the output stages (on the cover, left cross-wall).