DTC 42

DTC 41, 42: Throttle Position Sensor System

Throttle Position Sensor System Circuit:

CIRCUIT OPERATION
The AWD-ECU receives a change in the output voltage from the throttle position sensor to determine the accelerator pedal opening angle.

DTC SET CONDITIONS
^ DTC 41 is set as excessively small output when the throttle position sensor output is below 0.2 volts in the idling state.
^ DTC 42 is set as excessively large output when the throttle position sensor output is more than 4.8 volts for more than 2 minutes continuously below a vehicle speed of 10 km/h (6.2 mph).

TROUBLESHOOTING HINTS (THE MOST LIKELY CAUSES FOR THIS CODE TO BE SET ARE:)
^ Malfunction of the throttle position sensor
^ Damaged harness and connector
^ Malfunction of the AWD-ECU

DIAGNOSIS
Required Special Tool:
^ MB991958: Scan Tool (M.U.T-III Sub Assembly)
^ MB991824: V.C.I.
^ MB991827: USB Cable
^ MB991911: Main Harness B

STEP 1. Using scan tool MB991958, read the MPI diagnostic trouble code.

CAUTION: 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) Check for MFI diagnostic trouble code.
4) Turn the ignition switch to the LOCK (OFF) position.
Q: Are DTCs P0121, P0122, P0123 set?
YES: Refer to Diagnostic Trouble Code Chart. Diagnostic Trouble Code Descriptions
NO: Go to Step 2.

STEP 2. Using scan tool MB991958, check data list item 13: Throttle Position Sensor Voltage.

CAUTION: 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 ON position.
3) Set scan tool MB991958 to the data reading mode.
^ Item 13: Throttle Position Sensor Voltage.
^ With the throttle valve in idle position, voltage should measure between 535 and 735 mV.
^ With the throttle valve in full-open position, voltage should measure between 4,500 and 5,500 mV.

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.
NO: Go to Step 3.

STEP 3. Measure the throttle position sensor output voltage at AWD-ECU connector C-138 by backprobing.








1) Turn the ignition switch to the ON position.
2) Measure the voltage between AWD-ECU connector C-139 terminal 39 and ground by backprobing.
^ With the throttle valve in idle position, voltage should measure between 0.535 and 0.735 volt.
^ With the throttle valve in full-open position, voltage should measure between 4.5 and 5.5 volts.

3) Turn the ignition switch to the LOCK (OFF) position.
Q: Is the measured voltage within the specified range?
YES: Go to Step 4.
NO: Go to Step 6.

STEP 4. Check AWD-ECU connector C-138 for loose, corroded or damaged terminals, or terminals pushed back in the connector.





Q: Are the connector and terminals in good condition?
YES: Go to Step 5.
NO: Repair or replace the damaged components.

STEP 5. Using scan tool MB991958, check data list item 13: Throttle Position Sensor Voltage.

CAUTION: 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 ON position.
3) Set scan tool MB991958 to the data reading mode.
^ Item 13: Throttle Position Sensor Voltage.
^ With the throttle valve in idle position, voltage should measure between 535 and 735 mV.
^ With the throttle valve in full-open position, voltage should measure between 4,500 and 5,500 mV.

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.
NO: Replace the AWD-ECU

STEP 6. Check the throttle position sensor.
Q: Is the check result normal?
YES: Go to Step 7.
NO: Repair or replace throttle position sensor.

STEP 7. Check throttle position sensor connector B-03, joint connector (6) C-105 and AWD-ECU connector C-138 for loose, corroded or damaged terminals, or terminals pushed back in the connector.











Q: Are the connectors and terminals in good condition?
YES: Go to Step 8.
NO: Repair or replace the damaged components.

STEP 8. Check the harness for open circuit or short circuit to ground between the throttle position sensor connector B-03 terminal 2 and AWD-ECU connector C-138 terminal 39.








Q: Are the connectors and terminals in good condition?
YES: Go to Step 5.
NO: Repair or replace the damaged components.