DTC P0651

DTC P0651  : Sensor Reference Voltage B Malfunction

NOTE:  Before you troubleshoot, review the general troubleshooting information .

DTC (PGM-FI)

1. Problem verification

   -1. Turn the vehicle to the ON mode.

   -2. Clear the DTC with the HDS.

   -3. Check for Pending or Confirmed DTCs with the HDS.

   DTC Description	Confirmed DTC	Pending DTC
   P0651 Sensor Reference Voltage B Malfunction

   Is DTC P0651 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 PCM and these parts. If the on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the on-board snapshot :

   • CMP sensor A
   • CMP sensor B
   • EGR valve
   • Rocker arm oil pressure sensor
   • Engine oil pressure sensor
   • Transmission fluid pressure sensor
   • APP sensor
   • A/C pressure sensor
   • EVAP leak check module
2. Determine possible failure area (VCC lines, others)

   -1. Turn the vehicle to the OFF (LOCK) mode.

   -2. Disconnect the following connectors.

   CMP sensor A 3P connector

   CMP sensor B 3P connector

   EGR valve 5P connector

   Rocker arm oil pressure sensor 3P connector

   Engine oil pressure sensor 3P connector

   Transmission fluid pressure sensor 3P connector

   APP sensor 6P connector

   A/C pressure sensor 3P connector

   EVAP leak check module 8P connector

   -3. Turn the vehicle to the ON mode.

   -4. Clear the DTC with the HDS.

   -5. Check for Pending or Confirmed DTCs with the HDS.

   DTC Description	Confirmed DTC	Pending DTC
   P0651 Sensor Reference Voltage B Malfunction

   Is DTC P0651 indicated?

   YES 

   Go to step 5.

   NO 

   Go to step 3.

3. Shorted part check:

   Check for Pending or Confirmed DTCs with the HDS while reconnecting these parts, one at a time:

   • CMP sensor A
   • CMP sensor B
   • EGR valve
   • Rocker arm oil pressure sensor
   • Engine oil pressure sensor
   • Transmission fluid pressure sensor
   • APP sensor
   • A/C pressure sensor
   • EVAP leak check module

   DTC Description	Confirmed DTC	Pending DTC
   P0651 Sensor Reference Voltage B Malfunction

   Is DTC P0651 indicated?

   YES 

   Replace the part that caused the DTC when it was reconnected.

   NO 

   Check for poor connections or loose terminals at the PCM and the following parts, then go to step 1.

   • CMP sensor A
   • CMP sensor B
   • EGR valve
   • Rocker arm oil pressure sensor
   • Engine oil pressure sensor
   • Transmission fluid pressure sensor
   • APP sensor
   • A/C pressure sensor
   • EVAP leak check module
4. Shorted wire check (VCC lines to power)

   -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 connectors.

   PCM connector A (50P)

   PCM connector E (80P)

   -4. Turn the vehicle to the ON mode.

   -5. Measure the voltage between these test points and body ground individually.

   Test condition

   Vehicle ON mode

   	CMP sensor A 3P connector: disconnected
   	CMP sensor B 3P connector: disconnected
   	EGR valve 5P connector: disconnected
   	Rocker arm oil pressure sensor 3P connector: disconnected
   	Engine oil pressure sensor 3P connector: disconnected
   	Transmission fluid pressure sensor 3P connector: disconnected
   	APP sensor 6P connector: disconnected
   	A/C pressure sensor 3P connector: disconnected
   	EVAP leak check module 8P connector: disconnected
   	PCM connector A (50P): disconnected
   	PCM connector E (80P): disconnected

   Connector	Terminal
   PCM connector A (50P)	No. 44
   PCM connector E (80P)	No. 63 and No. 77

   Is there any voltage?

   YES 

   Repair a short to power in the VCC wire(s) between the PCM (A44, E63, E77) and each part that was disconnected in step 2.

   NO 

   Go to step 5

5. Shorted wire check (VCC lines to ground)

   -1. Turn the vehicle to the OFF (LOCK) mode.

   -2. Measure the resistance between these test points and body ground individually.

   Test condition	Vehicle OFF (LOCK) mode
   	CMP sensor A 3P connector: disconnected
   	CMP sensor B 3P connector: disconnected
   	EGR valve 5P connector: disconnected
   	Rocker arm oil pressure sensor 3P connector: disconnected
   	Engine oil pressure sensor 3P connector: disconnected
   	Transmission fluid pressure sensor 3P connector: disconnected
   	APP sensor 6P connector: disconnected
   	A/C pressure sensor 3P connector: disconnected
   	EVAP leak check module 8P connector: disconnected
   	PCM connector A (50P): disconnected
   	PCM connector E (80P): disconnected

   Connector	Terminal
   PCM connector A (50P)	No. 44
   PCM connector E (80P)	No. 63 and No. 77

   Is there 1 MΩ or more?

   YES 

   The VCC wires are OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM .

   NO 

   Repair a short to ground in the VCC(s) wire between the PCM (A44, E63, E77) and each part that was disconnected in step 2.