Test 4: Tachometer
NOTE:
Before changing value on signal generator, turn ignition off.
Disconnect engine control module harness connectors. See Fig 1 . Connect Signal Generator (DTR-8416) between ground and terminal No. 17 at data link connector, according to manufacturer's instructions. See Fig 2 . Set voltage amplitude on signal generator to 10 volts. Turn ignition switch to RUN position. Ensure tachometer reading at each setting of signal generator is as specified. See TACHOMETER TESTING table. If tachometer readings are as specified, check Engine Control Module (ECM) output and repair as necessary. If tachometer readings are not as specified, repair wiring. See WIRING DIAGRAMS .
TACHOMETER TESTING
| Signal Generator Setting (Hz) | Tachometer Reading (RPM) | |
|---|---|---|
| 2.3L Engines | ||
| 30 | 1000 | |
| 130 | 4000 | |
| 200 | 6200 | |
| 2.8L Engines | ||
| 50 | 1000 | |
| 195 | 4000 | |
| 315 | 6400 | |