Instrument Cluster Test 3C - Tachometer Not Operating Properly
NOTE:
Perform INSTRUMENT CLUSTER TEST 1A
before proceeding with this test. For connector terminal identification, see CONNECTOR IDENTIFICATION in BODY CONTROL COMPUTER INTRODUCTION. Perform TEST VER-1A
after each repair.
CAUTION:
Always turn ignition switch to OFF position prior to disconnecting or connecting any module connector.
- Turn ignition to OFF (UNLOCK) position. Using scan tool, actuate gauges. If tachometer gradually steps up to 6000 RPM and then returns to zero, go to next step. If tachometer does not go to 6000 RPM, replace tachometer.
- Using scan tool, read Powertrain Control Module (PCM) status. If scan tool displays ACTIVE ON THE BUS, go to next step. If scan tool does not display ACTIVE ON THE BUS, go to NO RESPONSE TEST 3A .
- Start engine and allow it to idle. Using scan tool, read engine RPM. If scan tool RPM display matches tachometer RPM, tachometer is operating properly. If scan tool RPM display does not match tachometer RPM, replace BCM.