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Code 43: Throttle Switch

NOTE: Refer to illustration for ECU connector and terminal identification. See Figure . Power switch in integral to throttle switch.
  1. Turn ignition on. Backprobing ECU connector F120, measure voltage between ground and terminal No. 16 (Green/Red wire) of ECU. With throttle closed, voltage should be more than 8 volts. With throttle fully open, voltage should be less than one volt. If voltage is not as specified, go to next step. If voltage is as specified, check for poor ECU connector contact. Repair connector and/or wiring harness as necessary. If connector and wiring harness are okay, replace ECU.
  2. Turn ignition off. Disconnect throttle switch connector. Measure resistance between terminals No. 1 and 2 at throttle switch. See Figure . With throttle closed, resistance should be infinite. With throttle fully open, resistance should be less than one ohm. If resistance is as specified, go to next step. If resistance is not as specified, check throttle switch adjustment. See ADJUSTMENTS article. If throttle switch is adjusted properly, replace throttle switch.
  3. Disconnect ECU connectors. Measure resistance between ECU and throttle switch connectors and between ECU connector and ground. See the POWER SWITCH RESISTANCE SPECIFICATIONS  table. If resistance is as specified, check for poor ECU connector contact. Repair connector and/or wiring harness as necessary. If connector and wiring harness are okay, replace ECU. If resistance is not as specified, repair connector and/or wiring harness as necessary.
POWER SWITCH RESISTANCE SPECIFICATIONS

Measure Between Terminals Ohms
No. 1 (1) & No. 2 (2) Less Than One
No. 1 (1) & Ground Less Than 10
No. 16 (3) & Ground Infinite
No. 16 (3) & No. 1 (2) Less Than One
No. 10 (3) & Ground Less Than 10
No. 10 (3) & No. 2 (2) Less Than One
(1) Measure at ECU connector F119.
(2) Measure resistance at throttle switch connector. See Figure .
(3) Measure at ECU connector F120.