PGM-FI Control System - Troubleshooting Flowchart - ECU (cont'd)
6-22flowchartECU power/ground self-diagnosis flowchart. Wire colors referenced: GRN/ORN, BLK/RED, BRN/BLK, YEL/BLK; ground point G101; main relay; ECU terminals A2, A13, A15, A16, A18, B6.
Troubleshooting Flowchart - ECU (cont'd)
1
- Check Engine warning light is on. - LED doesn't blink.
2
Connect the PGM-FI test harness between the ECU and connector (page 6-19). Disconnect "B" connector from ECU only, not the main wire harness.
3
Turn the ignition switch ON.
4
Does Check Engine warning light remain on?
YES
Repair short to ground in GRN/ORN wire between ECU (B6) and combination meter.
NO
5
Reconnect "B" connector to ECU.
6
Connect following terminals individually to A2: A16, A18.
7
Is Check Engine warning light on?
NO
- Repair open in BLK/RED wire between ECU (A18) and G101. - Repair open in BRN/BLK wire between ECU (A16) and G101.
YES
8
Measure voltage between A13 (+), A15 (+) terminals and A18 (-) terminal.
9
Is there battery voltage?
NO
- Repair open in YEL/BLK wire between ECU (A13, A15) and main relay. - Check main relay and wiring connectors at main relay (page 6-79).
YES
(To page 6-23)