DTC Troubleshooting: P0816 (24-6)

DTC P0816: Short in Transmission Gear Selection Switch Downshift Switch Circuit, or Transmission Gear Selection Switch Downshift Switch Stuck ON NOTE:

- Record all freeze data and review General Troubleshooting Information before you troubleshoot.
- This code is caused by an electrical circuit problem and cannot be caused by a mechanical problem in the transmission.

1. Turn the ignition switch ON (II).

1. Shift to the P position.

1. Verify the transmission gear selection switch downshift switch inputs with the HDS in the A/T data list.

Is DOWNSHIFT SW ON?

YES | - | Go to Step 4 .
NO | - | Intermittent failure, the system is OK at this time. Check the ORN wire for an intermittent short to ground between the transmission gear selection switch and PCM.■

1. Turn the ignition switch OFF.

1. Disconnect the transmission gear selection switch connector.

1. Turn the ignition switch ON (II).

1. Verify the transmission gear selection switch downshift switch inputs with the HDS in the A/T data list.

Is DOWNSHIFT SW ON?

YES | - | Go to Step 8 .
NO | - | Replace the shift lever bracket base, then go to Step 12 .

1. Turn the ignition switch OFF.

1. Jump the SCS line with the HDS.

1. Disconnect PCM connector D (17P).

1. Check for continuity between transmission gear selection switch/park pin switch connector terminal No. 8 and body ground.

Is there continuity?

YES | - | Repair short to ground in the wire between PCM connector terminal D9 and the transmission gear selection switch connector, then go to Step 12 .
NO | - | Check for loose or poor connections at PCM connector terminal D9. If the connection is OK, update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM .■

1. Clear the DTC with the HDS.

1. Start the engine in the P position, wait for more than 10 seconds, then shift to the M position.

1. Push the shift lever toward shiftup position (+) slowly, and return to neutral position; repeat this test 10 times or more.

1. Pull the shift lever toward shiftdown position (−) slowly, and return to neutral position; repeat this test 10 times or more.

1. Monitor the OBD status for P0816 in the DTCs/Freeze Data in A/T Mode Menu for a pass/fail.

Does the result indicate a pass?

YES | - | The problem has been corrected.■
NO | - | Return to Step 1 and recheck.■