DTC 28
Park/Neutral Position Switch System Circuit
CIRCUIT OPERATION
- Battery positive voltage is applied to the Park/Neutral position switch (terminal 8) when the ignition switch is turned "ON."
- Battery positive voltage is applied to the PCM (terminal 101) when the selector lever is in the "P" range. The PCM judges that the selector lever is in the "P" range when the battery positive voltage is applied.
- Battery positive voltage is applied to the PCM [terminals 108, 121, 102, 109, 122 or 110] when the selector lever is in the "R" range ("N," "D" "3", "2" or "L" range). The PCM judges that the selector lever is in the "R" range ("N", "D", "3", "2" or "L" range) when the battery positive voltage is applied.
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.
Check for continuity between terminals for each selector position.
NOTE: For vehicles with sport mode, four positions (P, R, N, D) are used.
Q: Is the switch operating properly?
YES: Go to Step 2.
NO: Replace the Park/Neutral position switch.
STEP 2. Check connector B-41 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. Refer to Harness Connector Inspection.
STEP 3. Check connector C-61 <2.4L Engine> or C-63 <3.0L Engine> at PCM for damage.
Q: Is the connector in good condition?
YES: Go to Step 4.
NO: Repair or replace it. Refer to Harness Connector Inspection.
STEP 4. Check the switch output voltage at PCM connector C-61 <2.4L Engine> or C-63 <3.0L Engine> by backprobing. ("P" position)
1. Do not disconnect connector C-61 <2.4L Engine> or C-63 <3.0L Engine>.
2. Turn the ignition switch to "ON" position.
3. 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 volt or less.
- When selector lever position is "N," voltage should be 0.5 volt or less.
- When selector lever position is "D," voltage should be 0.5 volt or less.
- When selector lever position is "3," voltage should be 0.5 volt or less.
- When selector lever position is "2," voltage should be 0.5 volt or less.
- When selector lever position is "L," voltage should be 0.5 volt or less.
- When selector lever position is sport mode, voltage should be 0.5 volt or less.
Q: Is the voltage normal?
YES: Go to Step 7.
NO: Turn the ignition switch to "LOCK" (OFF) position. Go to Step 5.
STEP 5. Check harness for damage between Park/Neutral position switch connector B-41 terminal 3 and PCM connector C-63 terminal 101.
Q: Is the harness wire in good condition?
YES: Go to Step 6.
NO: Repair it.
STEP 6. Check connectors C-27 at intermediate connector and C-43 at combination meter for damage.
Q: Are the connectors in good condition?
YES: Repair it because of the harness damage between the Park/Neutral Position Switch connector B-41 terminal 3 and combination meter connector C-43 terminal 11.
NO: Repair or replace it. Refer to Harness Connector Inspection.
STEP 7. Check the switch output voltage at PCM connector C-61 <2.4L Engine> or C-63 <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 be 0.5 volt 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 volt or less.
- When selector lever position is "D," voltage should be 0.5 volt or less.
- When selector lever position is "3," voltage should be 0.5 volt or less.
- When selector lever position is "2," voltage should be 0.5 volt or less.
- When selector lever position is "L," voltage should be 0.5 volt or less.
- When selector lever position is sport mode, voltage should be 0.5 volt or less.
Q: Is the voltage normal?
YES: Go to Step 11.
NO: Turn the ignition switch to "LOCK" (OFF) position. Go to Step 8.
STEP 8. Check harness for damage between Park/Neutral position switch connector B-41 terminal 7 and PCM connector C-63 terminal 108.
Q: Is the harness wire in good condition?
YES: Go to Step 9.
NO: Repair it.
STEP 9. Check connectors C-27 at intermediate connector and C-43 at combination meter for damage.
Q: Are the connectors in good condition?
YES: Go to Step 10.
NO: Repair or replace it. Refer to Harness Connector Inspection.
STEP 10. Check harness for damage between Park/Neutral position switch connector B-41 term Install 7 and combination meter connector C-43 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-41 terminal 7.
NO: Repair it.
STEP 11. Check the switch output voltage at PCM connector C-61 <2.4L Engine> or C-63 <3.0L Engine> by backprobing. Measure the voltage between terminal 121 and ground by backprobing.
- When selector lever position is "P," voltage should be 0.5 volt or less.
- When selector lever position is "R," voltage should be 0.5 volt 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 volt or less.
- When selector lever position is "3," voltage should be 0.5 volt or less.
- When selector lever position is "2," voltage should be 0.5 volt or less.
- When selector lever position is "L," voltage should be 0.5 volt or less.
- When selector lever position is sport mode, voltage should be 0.5 volt or less.
Q: Is the voltage normal?
YES: Go to Step 14.
NO: Turn the ignition switch to "LOCK" (OFF) position. Go to Step 12.
STEP 12. Check harness for damage between Park/Neutral position switch connector B-41 terminal 4 and PCM connector C-43 terminal 121.
Q: Is the harness wire in good condition?
YES: Go to Step 13.
NO: Repair it.
STEP 13: Check connectors C-27 at intermediate connector C-43 at combination meter for damage.
Q: Are the connectors in good condition?
YES: Repair it because of the harness damage between the Park/Neutral Position Switch connector B-41 terminal 4 and combination meter connector C-43 terminal 9.
NO: Repair or replace it. Refer to Harness Connector Inspection.
STEP 14: Check the switch output voltage at PCM connector C-61 <2.4L Engine> or C-63 <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 be 0.5 volt or less.
- When selector lever position is "R," voltage should be 0.5 volt or less.
- When selector lever position is "N," voltage should be 0.5 volt 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 volt or less.
- When selector lever position is "2," voltage should be 0.5 volt or less.
- When selector lever position is "L," voltage should be 0.5 volt or less.
- When selector lever position is sport mode, voltage should be 0.5 volt or less.
Q: Is the voltage normal?
YES: Go to Step 21.
NO: Tern the ignition switch to "LOCK" (OFF) position. Go to Step 15.
STEP 15: Check harness for damage between Park/Neutral position switch connector B-41 terminal I and PCM connector C-63 terminal 102.
Q: Is the harness wire in good condition?
YES: Go to Step 16.
NO: Repair it.
STEP 16: Check connectors C-65 at shift switch assembly, C-27 at intermediate connector and C-41 at combination meter for damage.
Q: Are the connectors in good condition?
YES: Go to Step 17.
NO: Repair or replace it. Refer to Harness Connector Inspection.
STEP 17: Check harness for damage between Park/Neutral position switch connector B-41 terminal I and shift switch assembly connector C-65 terminal 1.
Q: Is the harness wire in good condition?
YES: Repair it because of harness damage between shift switch assembly connector C-65 terminal 2 and combination meter connector C-41 terminal 50.
NO: Repair it.
STEP 18: Check the switch output voltage at PCM connector C-61 <2.4L Engine> or C-63 <3.0L Engine> by backprobing.("T" position)
- When selector lever position is "P," voltage should be 0.5 volt or less.
- When selector lever position is "R," voltage should be 0.5 volt or less.
- When selector lever position is "N," voltage should be 0.5 volt or less.
- When selector lever position is "D," voltage should be 0.5 volt 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 volt or less.
- When selector lever position is "L," voltage should be 0.5 volt or less.
Q: Is the voltage normal?
YES: Go to Step 19.
NO: Tern the ignition switch to "LOCK" (OFF) position. Repair it because of the harness damage between the Park/Neutral position switch connector B-41 terminal 5 and PCM connector C-61 <2.0L Engine> or C-63 <3.0L Engine> terminal 109.
STEP 19: Check the switch output voltage at PCM connector C-61 <2.4L Engine> or C-63 <3.0L Engine> by backprobing.("2" position)
- When selector lever position is "P," voltage should be 0.5 volt or less.
- When selector lever position is "R," voltage should be 0.5 volt or less.
- When selector lever position is "N," voltage should be 0.5 volt or less.
- When selector lever position is "D," voltage should be 0.5 volt or less.
- When selector lever position is "3," voltage should be 0.5 volt 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 volt or less.
Q: Is the voltage normal?
YES: Go to Step 20.
NO: Tern the ignition switch to "LOCK" (OFF) position. Repair it because of the harness damage between the Park/Neutral position switch connector B-41 terminal 2 and PCM connector C-61 <2.0L Engine> or C-63 <3.0L Engine> terminal 122.
STEP 20: Check the switch output voltage at PCM connector C-61 <2.0L Engine> or C-63 <3.0L Engine> by backprobing.("L" position)
- When selector lever position is "P," voltage should be 0.5 volt or less.
- When selector lever position is "R," voltage should be 0.5 volt or less.
- When selector lever position is "N," voltage should be 0.5 volt or less.
- When selector lever position is "D," voltage should be 0.5 volt or less.
- When selector lever position is "3," voltage should be 0.5 volt or less.
- When selector lever position is "2," voltage should be 0.5 volt or less.
- When selector lever position is "L," voltage should be battery positive voltage.
Q: Is the voltage normal?
YES: Go to Step 21.
NO: Tern the ignition switch to "LOCK" (OFF) position. Repair it because of the harness damage between the Park/Neutral position switch connector B-41 terminal 6 and PCM connector C-61 <2.0L Engine> or C-63 <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 scan tool MB991502, always turn the ignition switch to "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502.
1. Connect scan tool MB991502 to the data link connector.
2. Turn the ignition switch to "ON" position.
3. Set 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 to confirm whether the MUT-II.(The sport mode is indicated as "D" on the MUT-II.)
4. Turn the ignition switch to "LOCK" (OFF) position.
Q: Is the switch operating properly?
YES: This malfunction can be intermittent. Refer to How to Use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction.
NO: Replace the PCM.