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DTC 27: Park/Neutral Position Switch System (Open 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 terminal 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 no Park/Neutral position switch input signal from any selector position for continuous period of thirty seconds, it is judged that there is an open circuit in the Park/Neutral position switch and diagnostic trouble code number "27" 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. Using scan tool MB991502, check dale list item 61: Park/Neutral Position Switch.
CAUTION: To prevent damage to scan tool MB991502, always turn the ignition switch to the "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 the "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," "1," and sport mode positions to confirm whether shown on the scan tool. (Vehicles with sport mode is indicated as "D" on the scan tool.)
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the switch operating properly?
YES: This malfunction can be intermittent.
NO: When indication disagrees at all positions: Go to Step 2. When indication disagrees at "P" position: Go to Step 6. When indication disagrees at "R" position: Go to Step 13.
^ When indication disagrees at "N" position: Go to Step 19. When indication disagrees at "D" position: Go to Step 25. When indication disagrees at "3" position: Go to Step 32.
^ When indication disagrees at "2" position: Go to Step 36. When indication disagrees at "L" position: Go to Step 40. When indication disagrees at sport mode position (agrees at "D" position): Go to Step 44.
STEP 2. 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 3.
NO: Replace the Park/Neutral position switch.
STEP 3. Check connectors B-41 at Park/Neutral position switch, C-28 at intermediate connector and C-112 at junction block for damage.
Q: Are the connectors in good condition?
YES: Go to Step 4.
NO: Repair or replace the defective connector(s).
STEP 4. Check harness for open circuit or short circuit to ground between Park/Neutral position switch connector B-41 terminal 8 and junction block connector C-112 terminal 12.
Q: Is the harness wire in good condition?
YES: Go to Step 5.
NO: Repair it.
STEP 5. 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 the "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 the "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," "1" and sport mode positions to confirm whether shown on the scan tool. (Vehicles with sport mode is indicated as "D" on the scan tool.)
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.
STEP 6. 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 7.
NO: Replace the Park/Neutral position switch.
STEP 7. Check connector B-41 at the Park/Neutral position switch for damage.
Q: Is the connector in good condition?
YES: Go to Step 8.
NO: Repair or replace it.
STEP 8. Check the switch output voltage at PCM connector C-61 <2.4L Engine> or C-63 <3.0L Engine> by backprobing.
1. Do not disconnect connector C-61 <2.4L Engine> or C-63 <3.0L Engine>.
2. Turn the ignition switch to the "ON" position.
3. Move the selector lever to the "P" position.
4. Measure the voltage between terminal 101 and ground by backprobing.
^ 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 12.
NO: Go to Step 9.
STEP 9. 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 10
NO: Repair or replace it.
STEP 10. Check harness for open circuit or short circuit to ground between Park/Neutral position switch connector B-41 terminal 3 and PCM connector C-61 <2.4L Engine> or C-63 <3.0L Engine> terminal 101
Q: Is the harness wire in good condition?
YES: Go to Step 11.
NO: Repair it.
STEP 11. Check connectors C-27 at intermediate connector and C-43 at combination meter for damage
Q: Are the connectors in good condition?
YES: Repair harness short circuit to ground between Park/ Neutral position switch connector B 41 terminal 3 and combination meter connector C-43 terminal 11.
NO: Repair or replace the defective connector(s).
STEP 12. 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 5.
NO: Repair or replace it.
STEP 13. 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 14.
NO: Replace the Park/Neutral position switch.
STEP 14. Check connector B-41 at the Park/Neutral position switch for damage.
Q: Is the connector in good condition?
YES: Go to Step 15.
NO: Repair or replace it.
STEP 15. Check the switch output voltage at PCM connector C-61 <2.4L Engine> or C-63 <3.0L Engine> by backprobing.
1. Do not disconnect connector C-61 <2.4L Engine> or C-63 <3.0L Engine>.
2. Turn the ignition switch to the "ON" position.
3. Move the selector lever to the "R" position.
4. Measure the voltage between terminal 108 and ground by backprobing.
^ 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 12.
NO: Go to Step 16.
STEP 16. 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 17
NO: Repair or replace it.
STEP 17. Check harness for open circuit or short circuit to ground between Park/Neutral position switch connector B41 terminal 7 and PCM connector C-61 <2.4L Engine> or C-63 <3.0L Engine> terminal 108
Q: Is the harness wire in good condition?
YES: Go to Step 18.
NO: Repair it.
STEP 18. Check connectors C-27 at intermediate connector C-43 at combination meter for damage
Q: Are the connectors in good condition?
YES: Repair harness short circuit to ground between Park/ Neutral position switch connector B41 terminal 7 and combination meter connector C-43 terminal 10.
NO: Repair or replace the defective connector(s).
STEP 19. 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 20.
NO: Replace the Park/Neutral position switch.
STEP 20. Check connector B 41 at the Park/Neutral position switch for damage.
Q: Is the connector in good condition?
YES: Go to Step 21.
NO: Repair or replace it.
STEP 21. Check the switch output voltage at PCM connector C-61 <2.4L Engine> or C-63 <3.0L Engine> by backprobing.
1. Do not disconnect connector C-61 <2.4L Engine> or C-63 <3.0L Engine>.
2. Turn the ignition switch to the "ON" position.
3. Move the selector lever to the "N" position.
4. Measure the voltage between terminal 121 and ground by backprobing.
^ 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 12.
NO: Go to Step 22.
STEP 22. 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 23
NO: Repair or replace it.
STEP 23. Check harness for open circuit or short circuit to ground between Park/Neutral position switch connector B-41 terminal 4 and PCM connector C-61 <2.4L Engine> or C-63 <3.0L Engine> terminal 121
Q: Is the harness wire in good condition?
YES: Go to Step 24.
NO: Repair it.
STEP 24. Check connectors C-27 at intermediate connector and C-43 at combination meter for damage
Q: Are the connectors in good condition?
YES: Repair harness short circuit to ground between Park/Neutral position switch connector B-41 terminal 4 and Combination meter C-43 terminal 9.
NO: Repair or replace the defective connector(s).