DTC 28
DTC 28: Park/Neutral Position Switch System (Short Circuit)DTC SET CONDITIONS
If the PCM detects more than one kind of park/ neutral position switch input signals for continuous period of thirty seconds, it is judged that there is a short circuit in the Park/Neutral position switch and diagnostic trouble code number "28" is output.
TROUBLESHOOTING HINTS (The most likely causes for this code to be set:)
- Malfunction of the Park/Neutral position switch
- Malfunction of the ignition switch
- Damaged harness, connector
- Malfunction of the PCM
DIAGNOSIS
Required Special Tool:
- MB991502: Scan Tool (MUT-II)
STEP 1. Check the Park/Neutral position switch.
Q: Is the switch operating properly?
YES: Go to Step 2.
NO: Replace the Park/Neutral position switch.
STEP 2. Check connector B-111 at the Park/Neutral position switch for damage.
Q: Is the connector in good condition?
YES: Go to Step 3.
NO: Repair or replace it.
STEP 3. Check connector C-121 <2.4L Engine> or C-123 <3.0L Engine> at PCM for damage.
Q: Is the connector in good condition?
YES: Go to Step 4.
NO: Repair or replace it.
STEP 4. Check the switch output voltage at PCM connector C-121 <2.4L Engine> or C-123 <3.0L Engine> by backprobing.
1) Do not disconnect connector C-121 <2.4L Engine> or C123 <3.0L Engine>.
2) Do not disconnect connector B-111 at Park/Neutral position switch.
3) Turn the ignition switch to the ON position.
4) Measure the voltage between terminal 101 and ground by backprobing.
- When selector lever position is P voltage should be battery positive voltage.
- When selector lever position is R voltage should be 0.5 volts or less.
- When selector lever position is N voltage should be 0.5 volts or less.
- When selector lever position is D voltage should be 0.5 volts or less.
- When selector lever position is 3 voltage should be 0.5 volts or less.
- When selector lever position is 2 voltage should be 0.5 volts or less.
- When selector lever position is L voltage should be 0.5 volts or less.
- When selector lever position is sport mode voltage should be 0.5 volts or less.
5) Turn the ignition switch to the LOCK (OFF) position.
Q: Is the voltage normal?
YES: Go to Step 7.
NO: Go to Step 5
1.
STEP 5. Check harness for damage between park/neutral position switch connector B-111 terminal 3 and PCM connector C-123 terminal 10 1.
Vehicles with sports modes
Q: Is the harness wire in good condition?
YES: Go to Step 6.
NO: Repair or replace it.
STEP 6. Check connectors C-24 at intermediate connector and C-103 at combination meter for damage. Vehicles with sports mode,
Q: Are the connectors in good condition?
YES: Repair it because of the harness damage between Park/Neutral Position Switch connector B-111 terminal 3 and combination meter connector C-103 terminal 11.
NO: Repair or replace it.
STEP 7. Check the switch output voltage at PCM connector C-121 <2.4L Engine> or C-123 <3.0L Engine> by backprobing.
1) Do not disconnect connector C-121 <2.4L Engine> or C123 <3.0L Engine>.
2) Do not disconnect connector B-111 at Park/Neutral position switch.
3) Turn the ignition switch to the "ON" position.
4) Measure the voltage between terminal 108 and ground by backprobing.
- When selector lever position is "P", voltage should be 0.5 volts or less.
- When selector lever position is "R", voltage should be battery positive voltage.
- When selector lever position is "N", voltage should be 0.5 volts or less.
- When selector lever position is "D", voltage should be 0.5 volts or less.
- When selector lever position is "3", voltage should be 0.5 volts or less.
- When selector lever position is "2", voltage should be 0.5 volts or less. Vehicles without sport mode>
- When selector lever position is "L", voltage should be 0.5 volts or less.
- When selector lever position is sport mode, voltage should be 0.5 volts or less.
5) Turn the ignition switch to the "LOCK"(OFF) position.
Q: Is the voltage normal?
YES: Go to Step 11.
NO: Go to Step 8
STEP 8. Check harness for damage between Park/Neutral position switch connector B-111 terminal 7 and PCM connector C-123 terminal 108.
Q: Is the harness wire in good condition?
YES: Go to Step 9.
NO: Repair or replace it.
STEP 9. Check connectors C-24 at intermediate connector and C-103 at combination meter for damage.
Q: Are the connectors in good condition?
YES: Go to Step 10.
NO: Repair or replace it.
STEP 10. Check harness for damage between Park/Neutral position switch connector B-111 terminal 7 and combination meter connector C-103 terminal 10.
Q: Is the harness wire in good condition?
YES: Repair it because of the connector and the harness damage between output signal of Park/Neutral position switch connector B-111 terminal 7.
NO: Repair or replace it.
STEP 11. Check the switch output voltage at PCM connector C-121 <2.4L Engine> or C-123 <3.0L Engine> by backprobing.
1) Do not disconnect connector C-121 <2.4L Engine> or C 123 <3.0L Engine>.
2) Do not disconnect connector B-111 at Park/Neutral position switch.
3) Turn the ignition switch to the "ON" position.
4) Measure the voltage between terminal 121 and ground by backprobing.
- When selector lever position is "P", voltage should be 0.5 volts or less.
- When selector lever position is "R", voltage should be 0.5 volts or less.
- When selector lever position is "N", voltage should be battery positive voltage.
- When selector lever position is "D", voltage should be 0.5 volts or less.
- When selector lever position is "3", voltage should be 0.5 volts or less.
- When selector lever position is "2", voltage should be 0.5 volts or less.
- When selector lever position is "L", voltage should be 0.5 volts or less.
5) Turn the ignition switch to the "LOCK"(OFF) position.
Q: Is the voltage normal?
YES: Go to Step 14.
NO: Go to Step 12
STEP 12. Check harness for damage between Park/Neutral position switch connector B-111 terminal 4 and PCM connector C-103 terminal 121.
Q: Is the harness wire in good condition?
YES: Go to Step 1 3.
NO: Repair or replace it.
STEP 13. Check connectors C-24 at intermediate connector C-103 at combination meter for damage.
Q: Are the connectors in good condition?
YES: Repair it because of the harness damage between Park/Neutral Position Switch connector B-111 terminal 4 and combination meter connector C-103 terminal 9.
NO: Repair or replace it.
STEP 14. Check the switch output voltage at PCM connector C-121 <2.4L Engine> or C-123 <3.0L Engine> by backprobing.
1) Do not disconnect connector C-121 <2.4L Engine> or C 123 <3.0L Engine>.
2) Do not disconnect connector B-111 at Park/Neutral position switch.
3) Turn the ignition switch to the "ON" position.
4) Measure the voltage between terminal 102 and ground by backprobing.
- When selector lever position is "P", voltage should be 0.5 volts
- When selector lever position is "R", voltage should be 0.5 volts or less.
- When selector lever position is "N", voltage should be 0.5 volts or less.
- When selector lever position is "D", voltage should be battery positive voltage.
- When selector lever position is "3", voltage should be 0.5 volts or less. Vehicles without sport mode>
- When selector lever position is "2", voltage should be 0.5 volts or less.
- When selector lever position is "L", voltage should be 0.5 volts or less.
- When selector lever position is sport mode, voltage should be 0.5 volts or less.
5) Turn the ignition switch to the "LOCK"(OFF) position.
Q: Is the voltage normal?
YES: Go to Step 21 Vehicles with sports mode>. Go to Step 18
NO: Go to Step 15 Vehicles with sports mode> Repair it because of the harness damage between Park/Neutral Position Switch connector B-111 terminal 1 and PCM connector C-121 <2.4L Engine> or C-123 <3.0L Engine> terminal 102.
STEP 15. Check harness for damage between Park/Neutral position switch connector B-111 terminal 1 and PCM connector C-123 terminal 102.
Q: Is the harness wire in good condition?
YES: Go to Step 16.
NO: Repair or replace it.
STEP 16. Check connectors C-132 at shift switch assembly, C-24 at intermediate connector and C-101 at combination meter for damage.
Q: Are the connectors in good condition?
YES: Go to Step 17.
NO: Repair or replace it.
STEP 17. Check harness for damage 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: Repair it because of harness damage between shift switch assembly connector C-132 terminal 2 and combination meter connector C-101 terminal 50.
NO: Repair or replace it.
STEP 18. Check the switch output voltage at PCM connector C-121 <2.4L Engine> or C-123 <3.0L Engine> by backprobing. Vehicles without sport modes
1) Do not disconnect connector C-121 <2.4L Engine> or C123 <3.0L Engine>.
2) Do not disconnect connector B-111 at Park/Neutral position switch.
3) Turn the ignition switch to the "ON" position.
4) Measure the voltage between terminal 109 and ground by backprobing.
- When selector lever position is "P" voltage should be 0.5 volts or less.
- When selector lever position is "R" voltage should be 0.5 volts or less.
- When selector lever position is "N" voltage should be 0.5 volts or less.
- When selector lever position is "D" voltage should be 0.5 volts or less.
- When selector lever position is "3" voltage should be battery positive voltage.
- When selector lever position is "2" voltage should be 0.5 volts or less.
- When selector lever position is "L" voltage should be 0.5 volts or less.
5) Turn the ignition switch to the "LOCK"(OFF) position.
Q: Is the voltage normal?
YES: Go to Step 19.
NO: Repair it because of the harness damage 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.
STEP 19. Check the switch output voltage at PCM connector C-121 <2.4L Engine> or C-123 <3.0L Engine> by backprobing. Vehicles without sport modes
1) Do not disconnect connector C-121 <2.4L Engine> or C123 <3.0L Engine>.
2) Do not disconnect connector B-111 at Park/Neutral position switch.
3) Turn the ignition switch to the "ON" position.
4) Measure the voltage between terminal 122 and ground by backprobing.
- When selector lever position is "P", voltage should be 0.5 volts or less.
- When selector lever position is "R", voltage should be 0.5 volts or less.
- When selector lever position is "N", voltage should be 0.5 volts or less.
- When selector lever position is "D", voltage should be 0.5 volts or less.
- When selector lever position is "3", voltage should be 0.5 volts or less.
- When selector lever position is "2", voltage should be battery positive voltage.
- When selector lever position is "L", voltage should be 0.5 volts or less.
5) Turn the ignition switch to the "LOCK"(OFF) position.
Q: Is the voltage normal?
YES: Go to Step 20.
NO: Repair it because of the harness damage 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.
STEP 20. Check the switch output voltage at PCM connector C-121 <2.4L Engine> or C-123 <3.0L Engine> by backprobing.
1) Do not disconnect connector C-121 <2.4L Engine> or C123 <3.0L Engine>.
2) Do not disconnect connector B-111 at Park/Neutral position switch.
3) Turn the ignition switch to the "ON" position.
4) Measure the voltage between terminal 110 and ground by backprobing.
- When selector lever position is "P", voltage should be 0.5 volts or less.
- When selector lever position is "R", voltage should be 0.5 volts or less.
- When selector lever position is "N", voltage should be 0.5 volts or less.
- When selector lever position is "D", voltage should be 0.5 volts or less.
- When selector lever position is "3", voltage should be 0.5 volts or less.
- When selector lever position is "2", voltage should be 0.5 volts or less.
- When selector lever position is "L", voltage should be battery positive voltage.
5) Turn the ignition switch to the "LOCK"(OFF) position.
Q: Is the voltage normal?
YES: Go to Step 21.
NO: Repair it because of the harness damage 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.
STEP 21. Using scan tool MB991502, check data list item 61: Park/Neutral Position Switch.
CAUTION: To prevent damage to the scan tool MB991502, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting the scan tool MB991502.
1) Connect scan tool MB991502 to the data link connector.
2) Turn the ignition switch to the "ON" position.
3) Set scan tool MB991502 to the 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 to confirm whether the MUT-II. (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: This malfunction can be intermittent.
NO: Replace the PCM.