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Test D6 - Shift Indicator Light (SIL)

Fig 1: Shift Indicator Light (SIL) Circuits
G72369
  1. Checking SIL Operation  - Inspect SIL while driving vehicle. SIL should turn on when optimum shift RPM is reached in each gear. Light should be off in highest gear. If SIL light is always on, check for a short in SIL circuit. If light is always off, check for an open in SIL circuit. If light is always on, go to step 6). If light is always off, go to next step.
  2. Checking SIL Circuit Fuse  - Turn key off and wait 10 seconds. Remove and inspect SIL circuit fuse (No. 18). If fuse is okay, go to next step. If fuse is blown, repair ground short between bulb and fuse, verify system operation.
  3. Check SIL Bulb  - Turn key off. Remove and inspect SIL bulb. If bulb is okay, go to next step. Replace bulb if necessary.
  4. Checking SIL Dimmer Relay Continuity  - Turn key off. Disconnect SIL dimmer relay. Set DVOM on 200-ohm scale. Measure resistance between dimmer relay pins No. 3 and 5. If resistance is less than 5 ohms, go to next step. If resistance is greater than 5 ohms, replace dimmer relay, and check operation.
  5. Checking Dimmer Relay Function  - Turn key off, and disconnect dimmer relay. Connect a 12-volt circuit between Pins No. 1 and 2. Set DVOM on 200-ohm scale. Measure resistance between Pins No. 3 and 5. If resistance is 40-55 ohms, go to next step. If resistance is not to specification, replace dimmer relay, Check operation of SIL.
  6. Check Voltage at Dimmer Relay  - With KOEO, disconnect SIL Dimmer Relay. Set DVOM on 20-volt scale. Measure voltage between Test Pin No. 5 on relay harness connector, and battery ground. If voltage is less than 5 volts, repair circuit between relay and fuse. Check operation of SIL. If voltage is greater than 5 volts, go to next step.
  7. Checking Voltage at High Gear Switch  - With KOEO, disconnect high gear switch and set DVOM on 20-volt scale. Measure voltage between SIL dimmer relay of high gear switch and battery negative. If voltage is greater than 5-volts, go to next step. If voltage is less than 5 volts, repair circuit between high gear switch and dimmer relay. Check SIL operation.
  8. Checking Operation of High Gear Switch  - Turn key off and wait 10 seconds. Disconnect high gear switch. Set DVOM on 200-ohm scale. Measure resistance of High Gear Switch while shifting from highest gear to next lower gear. If circuit opens and closes, go to next step. If circuit does not open and close, replace switch.
  9. Checking Continuity of SIL Circuit  - Turn key off, and disconnect high gear switch. Install breakout box and leave ECA disconnected. Set DVOM on 200-ohm scale, and measure resistance between Test Pin No. 53 (No. 51 on 1.9L CFI, and No. 17 on 1.9L MPFI) and the ECA side of the high gear switch. If resistance is less than 5 ohms, reconnect high gear switch, shift transmission into high gear and go to next step. If resistance is more than 5 ohms, repair circuit between high gear switch and ECA.
  10. Checking Circuit For Short to Ground  - Turn key off, and place transmission in highest gear. Set DVOM on 200-ohm scale, and install breakout box, leaving ECA connected. Measure resistance between Test Pin No. 53 (No. 51 on 1.9L CFI, and No. 17 on 1.9L MPFI) and Test Pin No. 60. If resistance is less than 100K ohms, repair short between high gear switch and ECA. On 1.9L MPFI, also check STO circuit for short to ground. If resistance is greater than 100K ohms, rerun QUICK TEST  and check ECT and MAP circuits for influence on SIL system. If okay, replace ECA.
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