DTC 28
DTC 28: Park/Neutral Position Switch System (Short Circuit)Park/Neutral Position Switch System Circuit
Refer to DTC 27.
CIRCUIT OPERATION
Refer to DTC 27.
DTC SET CONDITIONS
If the PCM detects more than one park/neutral position switch input signal for thirty seconds, it is determined that there is a short circuit in the Park/ Neutral position switch and DTC 28 is set.
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
- Malfunction of the Park/Neutral position switch
- Malfunction of the ignition switch
- Damaged harness or connector
- Malfunction of the PCM
DIAGNOSIS
Required Special Tool:
- MB991502: Scan Tool (MUT-II)
STEP 1. Check the Park/Neutral position switch.
Measure the resistance between the terminals for each selector position as indicated in the table above.
NOTE: For vehicles with sport mode, four positions (P, R, N, D) are used.
Q: Is the measured resistance less than 2 ohms for each selector position?
YES: Go to Step 2.
NO: Replace the Park/Neutral position switch.
STEP 2. Check Park/Neutral position switch connector B-111 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 3.
NO: Repair or replace the damaged components.
STEP 3. Check PCM connector C-121 <2.4L Engine> or C123 <3.0L Engine> 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 4.
NO: Repair or replace the damaged components.
STEP 4. Measure the switch output voltage at PCM connector C-121 <2.4L Engine> or C-123 <3.0L Engine> by backprobing. ("P" position)
1) Do not disconnect connector C-121 <2.4L Engine> or C-123 <3.0L Engine>.
2) Turn the ignition switch to the "ON" position.
3) Measure the voltage between terminal 101 and ground by backprobing.
- When selector lever position is "P," voltage should measure battery positive voltage.
- When selector lever position is "R," voltage should measure 0.5 volt or less.
- When selector lever position is "N," voltage should measure 0.5 volt or less.
- When selector lever position is "D," voltage should measure 0.5 volt or less.
- When selector lever position is "3," voltage should measure 0.5 volt or less.
- When selector lever position is "2," voltage should measure 0.5 volt or less.
- When selector lever position is "L," voltage should measure 0.5 volt or less.
- When selector lever position is sport mode, voltage should measure 0.5 volt or less.
Q: Is the measured voltage within the specified range?
YES: Go to Step 8.
NO: Turn the ignition switch to the "LOCK" (OFF) position. Go to Step 5.
STEP 5. Check harness for open circuit or short circuit to ground between Park/Neutral position switch connector B-111 terminal 3 and PCM connector terminal 101.
Q: Is the harness wire in good condition?
YES: Go to Step 27.
NO: Repair or replace the harness wire.
STEP 6. Check intermediate connector C-24 and combination connector C-101 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 7.
NO: Repair or replace the damaged components.
STEP 7. Check harness for short circuit to ground between Park/Neutral position switch connector B-111 terminal 3 and combination connector C-101 terminal 13.
Q: Is the harness wire in good condition?
YES: Go to Step 27.
NO: Repair or replace the harness wire.
STEP 8. Measure the switch output voltage at PCM connector C-121 <2.41. Engine> or C-123 <3.0L Engine> by backprobing. ("R" position)
Measure the voltage between terminal 108 and ground by backprobing.
- When selector lever position is "P," voltage should measure 0.5 volt or less.
- When selector lever position is "R," When selector lever position is "P," voltage should measure battery positive voltage.
- When selector lever position is "N," voltage should measure 0.5 volt or less.
- When selector lever position is "D," voltage should measure 0.5 volt or less.
- When selector lever position is "3," voltage should measure 0.5 volt or less.
- When selector lever position is "2," voltage should measure 0.5 volt or less.
- When selector lever position is "L," voltage should measure 0.5 volt or less.
- When selector lever position is sport mode, voltage should measure 0.5 volt or less.
Q: Is the measured voltage within the specified range?
YES: Go to Step 12.
NO: Turn the ignition switch to the "LOCK" (OFF) position. Go to Step 9.
STEP 9. Check harness for open circuit or short circuit to ground between Park/Neutral position switch connector B-111 terminal 7 and PCM connector C-121 <2.4L Engine> or C-123 <3.0L Engine> terminal 108.
Q: Is the harness wire in good condition?
YES: Go to Step 27.
NO: Repair or replace the harness wire.
STEP 10. Check intermediate connector C-24 and combination connector C-101 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 11.
NO: Repair or replace the damaged components.
STEP 11. Check harness for short circuit to ground between Park/Neutral position switch connector B-111 terminal 7 and combination connector C-101 terminal 14.
Q: Is the harness wire in good condition?
YES: Go to Step 27.
NO: Repair or replace the harness wire.
STEP 12. Measure the switch output voltage at PCM connector C-121 <2.4L Engine> or C-123 <3.0L Engine> by backprobing. ("N" position)
Measure the voltage between terminal 121 and ground by backprobing.
- When selector lever position is "P," voltage should measure 0.5 volt or less.
- When selector lever position is "R," voltage should measure 0.5 volt or less.
- When selector lever position is "N," voltage should measure battery positive voltage.
- When selector lever position is "D," voltage should measure 0.5 volt or less.
- When selector lever position is "3," voltage should measure 0.5 volt or less.
- When selector lever position is "2," voltage should measure 0.5 volt or less.
- When selector lever position is "L," voltage should measure 0.5 volt or less.
- When selector lever position is sport mode, voltage should measure 0.5 volt or less.
Q: Is the measured voltage within the specified range?
YES: Go to Step 16.
NO: Turn the ignition switch to the "LOCK" (OFF) position. Go to Step 13.
STEP 13. Check harness for open circuit or short circuit to ground between Park/Neutral position switch connector B-111 terminal 4 and PCM connector C-121 <2.4L Engine> or C-123 <3.0L Engine> terminal 121.
Q: Is the harness wire in good condition?
YES: Go to Step 27.
NO: Repair or replace the harness wire.
STEP 14. Check intermediate connector C-24 and combination connector C-101 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 15.
NO: Repair or replace the damaged components.
STEP 15. Check harness for short circuit to ground between Park/Neutral position switch connector B-111 terminal 4 and combination connector C-101 terminal 15.
Q: Is the harness wire in good condition?
YES: Go to Step 27.
NO: Repair or replace the harness wire.
STEP 16. Measure the switch output voltage at PCM connector C-121 <2.4L Engine> or C-I23 <3.0L Engine> by backprobing. ("D" position)
Measure the voltage between terminal 102 and ground by backprobing.
- When selector lever position is "P," voltage should measure 0.5 volt or less.
- When selector lever position is "R," voltage should measure 0.5 volt or less.
- When selector lever position is "N," voltage should measure 0.5 volt or less.
- When selector lever position is "D," voltage should measure battery positive voltage.
- When selector lever position is "3 voltage should measure 0.5 volt or less.
- When selector lever position is "2," voltage should measure 0.5 volt or less.
- When selector lever position is "L," voltage should measure 0.5 volt or less.
- When selector lever position is sport mode, voltage should measure 0.5 volt or less.
Q: Is the measured voltage within the specified range?
YES: Go to Step 21.
NO: Turn the ignition switch to the "LOCK" (OFF) position. Go to Step 17.
STEP 17. Check harness for open circuit or short circuit to ground between Park/Neutral position switch connector B111 terminal 1 and PCM connector C-121 <2.4L Engine> or C-123 <3.0L Engine> terminal 102.
Q: Is the harness wire in good condition?
YES: Go to Step 27.
NO: Repair or replace the harness wire.
STEP 18. Check shift switch assembly connector C-132, intermediate connector C-24 and combination connector C-101 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 19.
NO: Repair or replace the damaged components.
STEP 19. Check harness for short circuit to ground between Park/Neutral position switch connector B-111 terminal 1 and shift switch assembly connector C-132 terminal 1.
Q: Is the harness wire in good condition?
YES: Go to Step 20.
NO: Repair or replace the harness wire.
STEP 20. Check harness for short circuit to ground between shift switch assembly connector C-1 32 terminal 2 and combination connector C-101 terminal 16.
Q: Is the harness wire in good condition?
YES: Go to Step 27.
NO: Repair or replace the harness wire.
STEP 21. Measure the switch output voltage at PCM connector C-121 <2.41L Engine> or C-123 <3.0L Engine> by backprobing. ("3 position)
Measure the voltage between terminal 109 and ground by backprobing.
- When selector lever position is "P," voltage should measure 0.5 volt or less.
- When selector lever position is "R," voltage should measure 0.5 volt or less.
- When selector lever position is "N,," voltage should measure 0.5 volt or less.
- When selector lever position is "D," voltage should measure 0.5 volt or less.
- When selector lever position is "3," voltage should measure battery positive voltage.
- When selector lever position is "2," voltage should measure 0.5 volt or less.
- When selector lever position is "L," voltage should measure 0.5 volt or less.
Q: Is the measured voltage within the specified range?
YES: Go to Step 23.
NO: Turn the ignition switch to the "LOCK" (OFF) position. Go to Step 22.
STEP 22. Check harness for open circuit or short circuit to ground between Park/Neutral position switch connector B-111 terminal 5 and PCM connector C-121 <2.4L Engine> or C-123 <3.0L Engine> terminal 109.
Q: Is the harness wire in good condition?
YES: Go to Step 27.
NO: Repair or replace the harness wire.
STEP 23. Measure the switch output voltage at PCM connector C-121 <2.4L Engine> or C-123 <3.0L Engine> by backprobing. ("2" position)
Measure the voltage between terminal 122 and ground by backprobing.
- When selector lever position is "P," voltage should measure 0.5 volt or less.
- When selector lever position is "R," voltage should measure 0.5 volt or less.
- When selector lever position is "N," voltage should measure 0.5 volt or less.
- When selector lever position is T," voltage should measure 0.5 volt or less.
- When selector lever position is "3," voltage should measure 0.5 volt or less.
- When selector lever position is "2," voltage should measure battery positive voltage.
- When selector lever position is "L," voltage should measure 0.5 volt or less.
Q: Is the measured voltage within the specified range?
YES: Go to Step 25.
NO: Turn the ignition switch to the "LOCK" (OFF) position. Go to Step 24.
STEP 24. Check harness for open circuit or short circuit to ground between Park/Neutral position switch connector B-111 terminal 2 and PCM connector C-121 <2.4L Engine> or C-123 <3.0L Engine> terminal 122.
Q: Is the harness wire in good condition?
YES: Go to Step 27.
NO: Repair or replace the harness wire.
STEP 25. Measure the switch output voltage at PCM connector C-121 <2.4L Engine> or C-123 <3.0L Engine> by backprobing. ("L" position)
Measured the voltage between terminal 110 and ground by backprobing.
- When selector lever position is "P," voltage should measure 0.5 volt or less.
- When selector lever position is "R," voltage should measure 0.5 volt or less.
- When selector lever position is "N," voltage should measure 0.5 volt or less.
- When selector lever position is "D," voltage should measure 0.5 volt or less.
- When selector lever position is "3," voltage should measure 0.5 volt or less.
- When selector lever position is "2," voltage should measure 0.5 volt or less.
- When selector lever position is "L," voltage should measure battery positive voltage.
Q: Is the measured voltage within the specified range?
YES: Go to Step 27.
NO: Turn the ignition switch to the "LOCK" (OFF) position. Go to Step 26.
STEP 26. Check harness for open circuit or short circuit to ground between Park/Neutral position switch connector B-111 terminal 6 and PCM connector C-121 <2.4L Engine> or C-123 <3.0L Engine> terminal 110.
Q: Is the harness wire in good condition?
YES: Go to Step 27.
NO: Repair or replace the harness wire.
STEP 27. Using scan tool M13991502, check data list item 61: Park/Neutral Position Switch.
CAUTION: To prevent damage to scan tool M13991502, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool M13991502.
1) Connect the scan tool MB991502 to the data link connector.
2) Turn the ignition switch to the "ON" position.
3) Set the scan tool MB991502 to data reading mode for item 61: Park/Neutral Position Switch.
- Move the selector lever to "P," "R," "N," "D," "3," "2," "L", and sport mode positions and confirm that the selected selector lever positions match the positions shown on the scan tool M13991502. (The sport mode is indicated as "D" on the MUT-II)
4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the switch operating properly?
YES: It can be assumed that this malfunction is intermittent.
NO: Replace the PCM.