Pinpoint Test I: Incorrect Tachometer Indication
Instrumentation, Message Center and Warning Chimes
Pinpoint Test I: Incorrect Tachometer Indication
Normal Operation
The PCM uses the Crankshaft Position (CKP) sensor to measure the engine rpm. The PCM sends the Instrument Cluster (IC) the data over the High Speed Controller Area Network (HS-CAN) communication bus to command the tachometer gauge according to the data.
If the IC (Instrument Cluster) does not receive the engine rpm data from the PCM for 5 seconds or less, the IC (Instrument Cluster) defaults the tachometer to the last setting, based upon the last known good rpm message.
If the IC (Instrument Cluster) does not receive the engine rpm data from the PCM for more than 5 seconds, the IC (Instrument Cluster) sets DTC U0100 in continuous memory and defaults the tachometer to 0 rpm.
If the IC (Instrument Cluster) receives invalid data for more than 5 seconds, the IC (Instrument Cluster) sets DTC U2196 and defaults the tachometer to 0 rpm
NOTE: If DTC U0100 is set in the IC (Instrument Cluster), other observable symptoms may be an inoperative speedometer, temperature gauge (non-hybrid) or odometer.
This pinpoint test is intended to diagnose the following:
- PCM concern
- IC (Instrument Cluster)
PINPOINT TEST I : INCORRECT TACHOMETER INDICATION
I1 RETRIEVE THE RECORDED DTCs FROM THE IC (Instrument Cluster) SELF-TEST
- Check for recorded IC (Instrument Cluster) DTCs from the self-test.
Are any DTCs recorded?
Yes
For DTC U0100, GO to Pinpoint Test AV Pinpoint Test AV: DTC U0100.
For all other DTCs, REFER to DTC Charts Instrumentation, Message Center and Warning Chimes.
No
GO to I2.
I2 RETRIEVE THE RECORDED DTCs FROM THE PCM KOEO (Key ON Engine OFF) SELF-TEST
- Check for recorded PCM DTCs from the Key ON Engine OFF (KOEO) self-test.
Are any PCM DTCs recorded?
Yes
REFER to Computers and Control Systems Information.
No
GO to I3.
I3 CARRY OUT THE TACHOMETER ACTIVE COMMAND USING THE SCAN TOOL
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: IC (Instrument Cluster) DataLogger.
- Select the IC (Instrument Cluster) tachometer (TACH) active command. Command the tachometer in increments of 10% while monitoring the tachometer. The tachometer indication should increase in increments of approximately 700 rpm (hybrid) or 800 rpm (non-hybrid) for each 10% change.
Does the tachometer indication increase within specifications?
Yes
GO to I4.
No
INSTALL a new IC (Instrument Cluster). REFER to Instrument Cluster (IC) . TEST the system for normal operation.
I4 CHECK THE ENGINE RPM INPUT USING THE IC (Instrument Cluster) DEALER TEST MODE
- Ignition ON.
- Enter Instrument Cluster (IC) Dealer Test Mode.
- NOTE: The display below uses xxx's to represent a numeric or alpha-numeric value. The value may display the same amount of characters represented by the xxx's or there may be more/less depending on the type of display. For example: txxx (base cluster) or TACHOMETER xxx RPM (message center cluster) may display T650 or TACHOMETER 650 RPM.
Scroll down to txxx (base cluster) or TACHOMETER xxx RPM (message center cluster).
- Start the engine and operate the engine at 1,000, 1,500 and 2,000 rpm while monitoring both the tachometer and the engine rpm input in the dealer test mode.
Does the engine rpm input agree with the position of the tachometer indication?
Yes
The tachometer is operating correctly at this time.
No
INSTALL a new IC (Instrument Cluster). REFER to Instrument Cluster (IC) . TEST the system for normal operation.