TEST
ACTION
APPLICABILITY
4
Turn the ignition off.
NOTE: Ensure the ECM harness connectors are connected.
Start the engine.
With a voltmeter set to measure frequency (Hz), measure the frequency of the Engine
Speed Sensor Signal circuit by back probing ECM C1 cavity 6.
Is the frequency between 26.0 and 34.0 Hz at idle?
All
Yes
→
Test Complete.
No
→
Replace and program the Engine Control Module in accordance
with the Service Information.
Perform ROAD TEST VERIFICATION - VER-2.
5
Turn the ignition off.
Disconnect the ECM harness connectors.
Disconnect the PCM harness connectors.
Turn the ignition on.
Measure the voltage on the Engine Speed Sensor Signal circuit.
Is the voltage above 6.0 volts?
All
Yes
→
Repair the Engine Speed Sensor Signal circuit for a short to
voltage.
Perform ROAD TEST VERIFICATION - VER-2.
No
→
Go To
6
6
Turn the ignition off.
Disconnect the ECM harness connectors.
Disconnect the PCM harness connectors.
Measure the resistance between ground and the Engine Speed Sensor Signal circuit.
Is the resistance above 100 kohms?
All
Yes
→
Go To
7
No
→
Repair the Engine Speed Sensor Signal circuit for a short to
ground.
Perform ROAD TEST VERIFICATION - VER-2.
7
Turn the ignition off.
Disconnect the ECM harness connectors.
Disconnect the PCM harness connectors.
Measure the resistance of the Engine Speed Sensor Signal circuit.
Is the resistance below 5.0 ohms?
All
Yes
→
Go To
8
No
→
Repair the Engine Speed Sensor Signal circuit for an open.
Perform ROAD TEST VERIFICATION - VER-2.
8
If there are no possible causes remaining, view repair.
All
Repair
Replace and program the Powertrain Control Module in accor-
dance with the Service Information.
Perform ROAD TEST VERIFICATION - VER-2.
264
DRIVEABILITY - DIESEL
*CHECKING THE TACHOMETER OPERATION —
Continued