Pinpoint Test F : The Tachometer Is Inoperative

Normal Operation and Fault Conditions
See Tachometer. REFER to: Instrument Panel Cluster (IPC) - System Operation and Component Description .

If the BCM does not receive the engine rpm data from the PCM, the BCM sets DTC U0100:00.

If the IPC does not receive the engine rpm data from the BCM for longer than 1 second, the IPC sets DTC U0100:00 and defaults the tachometer to 0 rpm.

Possible Sources
- BCM concern
- PCM concern
- IPC

F1 RETRIEVE THE RECORDED DIAGNOSTIC TROUBLE CODES (DTCS) FROM THE IPC (INSTRUMENT PANEL CLUSTER) SELF-TEST
- Using a diagnostic scan tool, perform the IPC self-test.
Are any Diagnostic Trouble Codes (DTCs) recorded?

Yes REFER to DTC Chart: IPC .

No GO to F2

F2 RETRIEVE THE RECORDED DIAGNOSTIC TROUBLE CODES (DTCS) FROM THE BCM (BODY CONTROL MODULE) SELF-TEST
- Using a diagnostic scan tool, perform the BCM self-test.
Are any Diagnostic Trouble Codes (DTCs) recorded?

Yes REFER to: Body Control Module (BCM) .

No GO to F3

F3 CARRY OUT THE TACHOMETER ACTIVE COMMAND USING A DIAGNOSTIC SCAN TOOL

Using a diagnostic scan tool, view the PCM Parameter Identifications (PIDs).

Select the IPC tachometer (TACH_IND) PID.

Command the tachometer to sweep on and off while monitoring the tachometer.

Does the tachometer increase from 0 rpm to 8, 000 rpm (gasoline engines) or 0 rpm to 6, 000 rpm (diesel engine) then return to 0 rpm?

Yes	DIAGNOSE any PCM Diagnostic Trouble Codes (DTCs). Refer to Engine Controls - Powertrain DTC Charts & Descriptions (Except Diesel & Hybrid) or Engine Controls - Powertrain DTC Charts & Descriptions (Diesel) .

No	Refer to IPC Guided Routine Testing .