DTC Troubleshooting: P0203
DTC P0203: No. 3 Cylinder Injector Circuit Malfunction
NOTE:
Before you troubleshoot, review the general troubleshooting information.
If DTC P0560, P068A, and/or P068B are stored at the same time as DTC P0203, troubleshoot those DTCs first, then recheck for DTC P0203.

DTC Description
Confirmed DTC
Pending DTC
P0203 No. 3 Cylinder Injector Circuit Malfunction
    

1.
Problem verification:

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

?2.
Clear the DTC with the HDS.


?3.
Start the engine (If the engine does not start, crank the engine for 20 seconds).

?4.
Check for Pending or Confirmed DTCs with the HDS.
DTC Description
Confirmed DTC
Pending DTC
P0203 No. 3 Cylinder Injector Circuit Malfunction
    

Is DTC P0203 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 injector 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.
Open wire check (INJ H3 line, INJ L3 line):

Open wire check (INJ H3 line, INJ L3 line)
?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. 14
Test point 2
PCM connector No. 1 (96P) No. 15

Is there continuity?

     
YES
     
     
     
The INJ H3 wire and the INJ L3 wire are not open. Go to step 5.
     
NO
     
     
     
Go to step 3.
3.
Open wire check (INJ H3 line):

Open wire check (INJ H3 line)
?1.
Disconnect the following connector.
No. 3 injector 2P connector

?2.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
PCM connector No. 1 (96P): disconnected
No. 3 injector 2P connector: disconnected
Test point 1
No. 3 injector 2P connector (female terminals) No. 2:
Test point 2
PCM connector No. 1 (96P) No. 15


Is there continuity?

     
YES
     
     
     
The INJ H3 wire is OK. Go to step 4.
     
NO
     
     
     
Repair an open in the INJ H3 wire between PCM connector No. 1 terminal No. 15 and the No. 3 injector.?
4.
Open wire check (INJ L3 line):

Open wire check (INJ L3 line)
?1.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
PCM connector No. 1 (96P): disconnected
No. 3 injector 2P connector: disconnected
Test point 1
No. 3 injector 2P connector (female terminals) No. 1:
Test point 2
PCM connector No. 1 (96P) No. 14


Is there continuity?

     
YES
     
     
     
The INJ L3 wire is OK. Replace all injectors as a set.?
     
NO
     
     
     
Repair an open in the INJ L3 wire between PCM connector No. 1 terminal No. 14 and the No. 3 injector.?
5.
Shorted wire check (INJ H3 line to power):

Shorted wire check (INJ H3 line to power)
?1.
Disconnect the following connector.
No. 3 injector 2P connector

?2.
Turn the vehicle to the ON mode.

?3.
Measure the voltage between test points 1 and 2.
Test condition
Vehicle ON mode
PCM connector No. 1 (96P): disconnected
No. 3 injector 2P connector: disconnected
Test point 1
PCM connector No. 1 (96P) No. 15
Test point 2
Body ground

Is there any voltage?

     
YES
     
     
     
Repair a short to power in the INJ H3 wire between PCM connector No. 1 terminal No. 15 and the No. 3 injector.?
     
NO
     
     
     
Go to step 6.
6.
Shorted wire check (INJ L3 line to power):

Shorted wire check (INJ L3 line to power)
?1.
Measure the voltage between test points 1 and 2.
Test condition
Vehicle ON mode
PCM connector No. 1 (96P): disconnected
No. 3 injector 2P connector: disconnected
Test point 1
PCM connector No. 1 (96P) No. 14
Test point 2
Body ground

Is there any voltage?

     
YES
     
     
     
Repair a short to power in the INJ L3 wire between PCM connector No. 1 terminal No. 14 and the No. 3 injector.?
     
NO
     
     
     
Go to step 7.
7.
Shorted wire check (INJ H3 line):

Shorted wire check (INJ H3 line)
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
PCM connector No. 1 (96P): disconnected
No. 3 injector 2P connector: disconnected
Test point 1
PCM connector No. 1 (96P) No. 15
Test point 2
Body ground

Is there continuity?

     
YES
     
     
     
Repair a short in the INJ H3 wire between PCM connector No. 1 terminal No. 15 and the No. 3 injector.?
     
NO
     
     
     
The INJ H3 wire is OK. Go to step 8.
8.
Shorted wire check (INJ L3 line):

Shorted wire check (INJ L3 line)
?1.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
PCM connector No. 1 (96P): disconnected
No. 3 injector 2P connector: disconnected
Test point 1
PCM connector No. 1 (96P) No. 14
Test point 2
Body ground

Is there continuity?

     
YES
     
     
     
Repair a short in the INJ L3 wire between PCM connector No. 1 terminal No. 14 and the No. 3 injector.?
     
NO
     
     
     
The INJ L3 wire is OK. 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 P0203 goes away and the PCM was substituted, replace the original PCM.?