Engine Speed (Cars With ETS)

FAULT DIAGNOSIS, ENGINE SPEED (cars with ETS)
Output Signal To ETS And The Tachometer

Fault Symptom.
The "TCS CTRL" warning lamp is on. The ETS system's emergency program is activated. The tachometer does not work.
Basic charging pressure only.
Uneven idling.
Stiff acceleration

Important: If the engine speed signal is permanently shorted to ground the engine will stop within a second or two of starting.

DIAGNOSTIC PROCEDURE

1. Checking Engine Speed
Connect the Scan Tool.
Start the car and run it at idling speed.
Select "ETS".
Select "CODE".
Select "249", which represents engine speed.
With a warmed-up engine running at idling speed the Scan Tool should show a reading of 850 rpm.
Compare the Scan Tool reading with the tachometer in the main instrument display panel.

If the Scan Tool and tachometer show about 850 rpm, fault diagnosis of the Traction Control System(TCS) is needed.

If the tachometer shows about 850 rpm but the Scan Tool shows 0 rpm, continue with point 2.

If the Scan Tool and tachometer show about 0 rpm, continue with point 3.





2. Checking The Wiring Harness
Check The Wiring between pin 2 of the tachometer and pin 12 of the ETS control module for continuity.

If the wiring is OK, fault diagnosis of the Traction Control System (TCS) is needed.

If the wiring system is not OK, rectify the fault.

3. Checking Diagnostic Trouble Codes
Obtain readouts of diagnostic trouble codes stored in the Trionic system.

If DTC P1322 is stored, refer to Before Replacing A Control Module.

If DTC P1322 is not stored, continue with point 4.

4. Checking The Wiring Harness
The probable cause is a break in the wiring between pin 58 of the Trionic control module and pin 2 of the tachometer.
Check The Wiring harness for continuity.

If the wiring is OK, refer to Before Replacing A Control Module.

If the wiring is not OK, rectify the fault.