Instrument Cluster Test 3C - Tachometer Not Operating Properly
NOTE:
Perform INSTRUMENT CLUSTER TEST 1A
before proceeding with this test. For connector terminal ID, see CONNECTOR IDENTIFICATION
and WIRING DIAGRAMS
. Perform TEST VER-1A - VERIFICATION PROCEDURE
after each repair.
CAUTION:
Always turn ignition switch to OFF position prior to disconnecting or connecting any module connector.
- Turn ignition on. 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, recalibrate gauges using scan tool. If tachometer still does not function correctly, replace gauge pack and recalibrate.
- 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 VEHICLE COMMUNICATIONS TESTS .
- Start and idle engine. Using scan tool, select MIC, then MONITORS, then ENGINE INFOR. Read engine RPM. If scan tool RPM display matches tachometer RPM, tachometer is currently operating properly. If scan tool RPM display does not match tachometer RPM, replace Powertrain Control Module (PCM). PCM is located next to power distribution center.