Pinpoint Test E: The Tachometer Is Inoperative
- E1 CARRY OUT THE TACHOMETER ACTIVE COMMAND USING THE DIAGNOSTIC TOOL
- Key in ON position.
- Enter the following diagnostic mode on the scan tool: Instrument Cluster Active Command.
- Select the instrument cluster tachometer active command. Trigger the tachometer and scroll in increments of 10%. Monitor the tachometer gauge. The tachometer indication should increase in increments of approximately 800 rpm for each 10% change.
- Does the tachometer indication increase within specifications?
Yes : GO to E2.
No : GO to E3.
- E2 MONITOR THE ENGINE RPM PID
- Enter the following diagnostic mode on the scan tool: PCM PID.
- Monitor the engine RPM PID while varying the engine speed.
- Does the engine RPM PID match the tachometer reading on the instrument cluster?
Yes : REFER to the INTRODUCTION - GASOLINE article or INTRODUCTION -- HYBRID ESCAPE & HYBRID MARINER article to continue diagnosis.
No : GO to E3.
- E3 CHECK FOR CORRECT INSTRUMENT CLUSTER OPERATION
- Disconnect the instrument cluster connector.
- Check for:
- corrosion
- pushed-out pins
- Connect the instrument cluster connector and make sure it seats correctly.
- Operate the system and determine if the concern is still present.
- Is the concern still present?
Yes : INSTALL a new instrument cluster. REFER to INSTRUMENT CLUSTER in this article. TEST the system for normal operation.
No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.