DIAGNOSIS Required Special Tools: • MB991958: Scan Tool (MUT-III Sub Assembly) MB991824: V.C.I MB991827: USB Cable MB991911: Main Harness B

STEP 1. Using scan tool MB991958, check data list item 14: Throttle Position Sensor.

To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958. (1) Connect scan tool MB991958 to the data link connector. (2) Turn the ignition switch to the "ON" position. (3) Set scan tool MB991958 to the data reading mode for item 14, Throttle Position Sensor. • With the throttle valve in the idle position, voltage should measure between 0.535 and 0.735 volt. • With the throttle valve in the full-open position, voltage should measure between 4.5 and 5.5 volts. (4) Turn the ignition switch to the "LOCK" (OFF) position. Q: Is the sensor operating properly? YES: It can be assumed that this malfunction is intermittent. Refer to GROUP 00, How to Use Troubleshooting/Inspection Service Points . NO: Go to Step 2.

STEP 2. Check connector A-41 at throttle position sensor for damage.

Q: Is the connector in good condition? YES: Go to Step 3. NO: Repair or replace it. Refer to GROUP 00E, Harness Connector Inspection . Then go to Step 8.

STEP 3. Check for continuity at throttle position sensor harness side connector A-41.

(1) Disconnect the connector A-41 and measure at the harness side.

(2) Measure the continuity between terminal No. 1 and ground. • Should be less than 2 ohms. Q: Does continuity exist? YES: Go to Step 6. NO: Go to Step 4.

STEP 4. Check connector C-90 at PCM for damage.

Q: Is the connector in good condition? YES: Go to Step 5. NO: Repair or replace it. Refer to GROUP 00E, Harness Connector Inspection . Then go to Step 8.

STEP 5. Check for open circuit and harness damage between throttle position sensor connector A-41 (terminal No. 1) and PCM connector C-90 (terminal No. 57).

NOTE: Check harness after checking intermediate connector C-71. If intermediate connector is damaged, repair or replace it. Refer to GROUP 00E, Harness Connector Inspection . Then go to Step 14. Q: Is the harness wire in good condition? YES: Replace the PCM. Then go to Step 8. NO: Repair it. Then go to Step 8.

STEP 6. Check the throttle position sensor.

(1) Disconnect the connector A-41.

(2) Measure the resistance between throttle position sensor side connector terminal No. 1 and No. 4. Standard value: 3.5 - 6.5 kΩ (3) Measure resistance between the throttle position sensor side connector terminal No. 1 and No. 3. (4) Move the throttle valve from the idle position to the full-open position. • Resistance should change smoothly in proportion to the opening angle of the throttle valve. Q: Is the resistance normal? YES: Go to Step 7. NO: Replace the throttle position sensor. Refer to Throttle Body Assembly - Disassembly And Assembly . Then go to Step 8.

STEP 7. Using scan tool MB991958, check data list item 14: Throttle Position Sensor.

To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958. (1) Connect scan tool MB991958 to the data link connector. (2) Turn the ignition switch to the "ON" position. (3) Set scan tool MB991958 to the data reading mode for item 14, Throttle Position Sensor. • With the throttle valve in the idle position, voltage should measure between 0.535 and 0.735 volt. • With the throttle valve in the full-open position, voltage should measure between 4.5 and 5.5 volts. (4) Turn the ignition switch to the "LOCK" (OFF) position. Q: Is the sensor operating properly? YES: It can be assumed that this malfunction is intermittent. Refer to GROUP 00, How to Use Troubleshooting/Inspection Service Points . NO: Replace the PCM. Then go to Step 8.