DTC Troubleshooting: P0812
DTC P0812: Transmission Range Switch ATP R Switch
NOTE:
Before you troubleshoot, record all freeze data and any on-board snapshot with the HDS, and review the General Troubleshooting Information.
This code is caused by an electrical circuit problem and cannot be caused by a mechanical problem in the transmission.

DTC Description
Confirmed DTC
Pending DTC
Freeze Frame
P0812 Transmission Range Switch ATP R Switch
      

1.
Problem verification:

Problem verification
?1.
Press the engine start/stop button to select the ON mode.

?2.
Check the parameter(s) below with the HDS with the shift lever in R.
Signal
Threshold
Current conditions
Values
Unit
Values
Unit
A/T R Switch
ON
      

Do the current condition(s) match the threshold?

     
YES
     
     
     
Intermittent failure, the system is OK at this time.?
     
NO
     
     
     
The failure is duplicated. Go to step 2.
2.
Determine possible failure area (transmission range switch, ATPR line):

Determine possible failure area (transmission range switch, ATPR line)
?1.
Press the engine start/stop button to select the OFF mode.

?2.
Disconnect the following connector.

?3.
Connect terminals A and B with a jumper wire.
Terminal A
Transmission range switch 10P connector No. 8 (WHT)
Terminal B
Body ground


?4.
Press the engine start/stop button to select the ON mode.

?5.
Check the parameter(s) below with the HDS.
Signal
Threshold
Current conditions
Values
Unit
Values
Unit
A/T R Switch
ON
      

Do the current condition(s) match the threshold?

     
YES
     
     
     
     
NO
     
     
     
Go to step 3.
3.
Open wire check (ATP-R, ATPR line):

Open wire check (ATP-R, ATPR line)
?1.
Press the engine start/stop button to select the OFF mode.

?2.
Jump the SCS line with the HDS.


?3.
Disconnect the following connector.

?4.
Check for continuity between test points 1 and 2.
Test condition
OFF mode
 
Transmission range switch 10P connector: disconnected
 
PCM connector A (51P): disconnected
Test circuit
ATP-R, ATPR
Test point 1
PCM connector A (51P) No. 16 (GRN)
Test point 2
Body ground


Is there continuity?

     
YES
     
     
     
     
NO
     
     
     
Repair an open in the ATP-R, ATPR wire between the transmission range switch and the PCM, then do the repair verification.
Repair verification (OBD STATUS check):

?1.
Reconnect all connectors.

?2.
Exit the SCS mode with the HDS.


?3.
Press the engine start/stop button to select the ON mode.

?4.
Clear the DTC with the HDS.


?5.
Test-drive the vehicle with the shift lever in R at speeds below 3 mph (5 km/h) for at least 2 seconds. Then increase the speed and drive over 3 mph (5 km/h) for at least 2 seconds.

?6.
Monitor the OBD STATUS for P0812 in the DTCs MENU with the HDS.
DTC Description
OBD Status
P0812 Transmission Range Switch ATP R Switch
  


Does the HDS indicate PASSED, FAILED, or NOT COMPLETED?

     
PASSED
     
     
     
Troubleshooting is complete. If the PCM was substituted, replace the original PCM. Check for other DTCs after this troubleshooting. If any other Pending or Confirmed DTCs were indicated, go to the indicated DTC's troubleshooting.?
     
FAILED
     
     
     
Troubleshooting is incomplete. Check for poor connections and loose terminals between the transmission range switch and the PCM, then go to step 1 and recheck. If the PCM was updated, substitute a known-good PCM, and check the OBD STATUS again.
     
NOT COMPLETED
     
     
     
Repair verification is incomplete. Meet the test condition, and check the OBD STATUS again.