TEST 4 (TPS Wide Open Throttle)
- Ground Violet and Black wire terminals of ALDL connector with engine idling. Connect dwell meter (6-cyl. scale). Warm engine until dwell starts to vary.
- Connect jumper between ECM terminals No. 5 and 22 of C-45 and note dwell. See Fig 1
. If dwell changes to less than 20 degrees, go to step 3). If dwell does not change, check ECM connector or replace ECM.
- Remove jumper wire. With ignition on and engine off, check voltage from ECM terminals No. 5 to 22 while depressing accelerator pedal. If there is no voltage, go to step 4). If voltage decreased from greater than 3 volts (idle) to less than 3 volts (wide open throttle), perform FEEDBACK PRELIMINARY CHECK at the beginning of this section.
- If voltage is greater than 6 volts, go to step 5). If voltage is less than 2 volts, go to step 6). If voltage is between 2-6 volts, check TPS assembly.
- Repair short to battery wire to ECM connector C-45 terminals No. 5, 7 or 22.
- Check open wire or grounded wire to ECM connector C-45 terminals No. 5 or 7. If okay, check TPS assembly.
Courtesy of ISUZU MOTOR CO.