Diagnosis & Repair (Using Toyota Hand-Held Tester)

Connect Toyota hand-held tester to Data Link Connector (DLC) No. 3. See Figure. Turn ignition on. Using hand-held tester, monitor APP sensor voltage for VPA and VPA2 circuits. See ACCELERATOR PEDAL POSITION SENSOR VOLTAGE table. If voltage is not as specified, go to next step. If voltage is as specified, replace ECM.

ACCELERATOR PEDAL POSITION SENSOR VOLTAGE

Accelerator Pedal		Volts
Depressed
VPA Circuit		3.2-4.8
VPA2 Circuit		4.7-5.1
Released
VPA Circuit		0.3-0.9
VPA2 Circuit		1.8-2.7

Access ECM behind glove box. See Figure. Turn ignition on. Using DVOM, backprobe ECM harness connector and measure voltage between terminals No. 2 (Blue/Red wire) and No. 18 (Brown/White wire) at ECM harness connector E6. See Figure. If voltage is 4.5-5.5 volts, go to next step. If voltage is not 4.5-5.5 volts, replace ECM.
Using DVOM, backprobe ECM harness connector and measure voltage between terminals No. 18 (Brown/White wire) and No. 21 (Red wire) at ECM harness connector E6. With fully closed throttle, voltage should be .3-.9 volt. With fully open throttle, voltage should be 3.2-4.8 volts. Using DVOM, backprobe ECM harness connector and measure voltage between terminals No. 18 (Brown/White wire) and No. 9 (Red/Black wire) at ECM harness connector E6. With fully closed throttle, voltage should be 1.8-2.7 volts. With fully open throttle, voltage should be 4.7-5.1 volts. If voltage readings are not as specified, go to next step. If voltage readings are as specified, replace ECM.
Check APP sensor. See THROTTLE BODY under IDLE CONTROL SYSTEMS in SYSTEM & COMPONENT TESTING - V6 & V8 article. If problem exists, replace APP sensor. If problem does not exist, repair open or short in wiring between ECM and APP sensor. See WIRING DIAGRAMS article.