Test sequence

WARNING: This page is about a different car, the 1999 Volkswagen Jetta, 1998 Volkswagen Jetta, and 1997 Volkswagen Jetta. However, it is still accessible from the selected car via links, so may be relevant.

Switch ignition off.
Disconnect RPM sensor harness connector (see Diesel Direct Fuel Injection (DFI) system components, overview ), connect multimeter, and check resistance between harness connector terminals 1 and 2.

Fig 1: Disconnecting Engine Speed (RPM) Sensor Harness Connector

Specification: 1000 to 1500 ohms (ohm)

If resistance is not as specified:

Replace engine speed sensor -G28-
See CRANKSHAFT, REMOVING AND INSTALLING
Display readiness code, see READINESS CODE, DISPLAYING .

If DTC memory was erased:

Create readiness code again, see READINESS CODE, SETTING (UP TO M.Y. 1997) .

If resistance is OK:

Connect VAG1598/18 test box to Diesel DFI ECM harness connector, see WIRING AND COMPONENT CHECKS, USING VAG1598/18 TEST BOX .
Check wiring for open circuit between 3-pin connector and test box, using wiring diagram:
- Terminal 1 + test box socket 33
- Terminal 2 + test box socket 8
- Terminal 3 + test box socket 1
- Wire resistance: 1.5 ohms (ohm) maximum
Check wiring for short circuit between terminals at 3 -pin connector, using wiring diagram.

Fig 2: Identifying Engine Speed (RPM) Sensor Pin Harness Connector Terminals

Specification: INFINITE ohm (no continuity)

If wiring is OK:

Replace Diesel DFI ECM -J248-, see item 3 .
Display readiness code, see READINESS CODE, DISPLAYING .

If DTC memory was erased:

Create readiness code again, see READINESS CODE, SETTING (UP TO M.Y. 1997) .