Engine Speed (RPM) Sensor, Checking
Engine speed (RPM) sensor, checkingThe engine speed sensor provides engine speed reference. If the component fails, the engine continues running using a back-up program. The signal from the needle lift sensor -G80- is used as a substitute.
Special tools, testers and auxiliary items:
-VAG1598/18 Test Box
-Fluke 83 multimeter (or equivalent)
-VW 1594 connector test kit
-Wiring diagram
Test Sequence:
-Switch OFF ignition
-Disconnect RPM sensor harness connector, connect multimeter, and check resistance between harness connector terminals 1 and 2
Specification: 1000 to 1500 Ohms
If resistance is not as specified:
-Replace engine speed sensor -G28-
-Display the readiness code
If DTC memory was erased:
-Create readiness code again
If resistance is OK:
-Connect VAG1598/18 test box to Diesel DFI ECM wiring harness connector
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 maximum.
Check wiring for short circuit between terminals at 3-pin connector, using wiring diagram
Specification: Infinite Ohms (no continuity)
If wiring is OK:
Replace Diesel DFI ECM -J248-
Display the readiness code
If DTC memory was erased:
- Create readiness code again