DTC Troubleshooting: P0121, P0221
DTC P0121: TP Sensor A Range/Performance Problem
DTC P0221: TP Sensor B Range/Performance Problem
NOTE: Before you troubleshoot, review the general troubleshooting information.

DTC Description
Confirmed DTC
Pending DTC
P0121 TP Sensor A Range/Performance Problem
    
P0221 TP Sensor B Range/Performance Problem
    

1.
Problem verification:

Problem verification
?1.
Turn the vehicle to the ON mode.

?2.
Clear the DTC with the HDS.


?3.
Start the engine.

?4.
Check for Pending or Confirmed DTCs with the HDS.
DTC Description
Confirmed DTC
Pending DTC
P0121 TP Sensor A Range/Performance Problem
    
P0221 TP Sensor B Range/Performance Problem
    

Is DTC P0121 and/or P0221 indicated?

     
YES
     
     
     
The failure is duplicated. Go to step 2.
     
NO
     
     
     
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the throttle body and the PCM. If the on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the on-board snapshot.?
2.
Determine possible failure area (throttle body, others):

Determine possible failure area (throttle body, others)
?1.
Check the parameter(s) below with the HDS.
Signal
Current conditions
Values
Unit
TP SENSOR A
    
TP SENSOR B
    

Are they the same voltage?

     
YES
     
     
     
Go to step 3.
     
NO
     
     
     
3.
Determine possible failure area (PCM, others):

Determine possible failure area (PCM, others)
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Jump the SCS line with the HDS, and wait more than 1 minute.


?3.
Disconnect the following connector.
PCM connector No. 1 (96P)

?4.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
PCM connector No. 1 (96P): disconnected
Test point 1
PCM connector No. 1 (96P) No. 88
Test point 2
PCM connector No. 1 (96P) No. 89

Is there continuity?

     
YES
     
     
     
Go to step 4.
     
NO
     
     
     
Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM, then recheck. If DTC P0121 and/or P0221 goes away and the PCM was substituted, replace the original PCM.?
4.
Shorted wire check (THL1 line to THL2 line):

Shorted wire check (THL1 line to THL2 line)
?1.
Disconnect the following connector.
Throttle body 6P connector

?2.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
PCM connector No. 1 (96P): disconnected
 
Throttle body 6P connector: disconnected
Test point 1
PCM connector No. 1 (96P) No. 88
Test point 2
PCM connector No. 1 (96P) No. 89

Is there continuity?

     
YES
     
     
     
Repair a short in the THL1 wire to the THL2 wire between the PCM and the throttle body.?
     
NO