Test sequence

• Disconnect harness connector for Pump-Injector Unit from cylinder head. Refer to item 10 in Component Locations, overview (vehicles with engine code BEW)  .

• Check resistance of Pump-Injector Unit valves between connector terminals.

Cyl. 1: Terminals 7 + 5

Cyl. 2: Terminals 7 + 3

Cyl. 3: Terminals 7 + 2

Cyl. 4: Terminals 7 + 6

Specified value: 0.1 to 1.0 Ω

• Check wires for short circuit to each other as well as to vehicle Ground (GND).

Specified value: ∞ Ω

If specified value is obtained:

• Check wires to control module according to wiring diagram. Refer to Check wires to control module  .

If specified value is not obtained:

• Remove upper toothed belt guard and cylinder head cover.
• Pry off connectors of all 4 pump-injector units using a screwdriver. In order to avoid canting, support opposite side of connector with light finger pressure.

• Check resistance of Pump-Injector Unit valves between connector terminals at Pump-Injector Unit valves.

Specified value: approx. 0.5 Ω

If specified value is not obtained:

• Replace malfunctioning Valve for pump/injector, cylinder 1 -N240- to Valve for pump/injector, cylinder 4 -N243-. Refer to Pump-Injector Unit, removing and installing  , removing and installing Pump-Injector Unit.
• Erase DTC memory of control module for Diesel-Direct fuel injection system. Refer to Diagnostic mode 4: Reset/erase diagnostic data  .
• Generate readiness code.

If specified value is obtained:

• Check wires between harness connector for Pump-Injector Unit and all 4 connectors (terminal 2) for open circuit.

Cyl. 1: Terminal 2 (gray) + terminal 5

Cyl. 2: Terminal 2 (red) + terminal 3

Cyl. 3: Terminal 2 (yellow) + terminal 2

Cyl. 4: Terminal 2 (white) + terminal 6

Wire resistance: max. 1.5 Ω

• Check wires between harness connector for Pump-Injector Unit and all 4 connectors (terminal 1) for open circuit.

Terminal 1 (brown) + terminal 7

Wire resistance: max. 1.5 Ω

• Check wires for short circuit to each other.

Specified value: ∞ Ω