Diagnostic Aids

The 5 V reference 1 circuit provides 5 V to the following sensors:

• Manifold absolute pressure (MAP) sensor
• Fuel tank pressure (FTP) sensor
• Accelerator pedal position (APP) sensor 2
• Engine oil pressure (EOP) sensor
• Air conditioning (A/C) refrigerant pressure sensor
• Camshaft position sensor

The 5 V reference 2 circuit provides 5 V to the following sensors:

• APP sensor 1
• Throttle position sensor 1 and 2
• Crankshaft position sensor
• Brake pedal position sensor

It may be possible to locate the fault by disconnecting one component at a time from the affected 5 V reference circuit while viewing the 5 V Reference circuit status parameter on the scan tool. The scan tool parameter will change from Fault to OK when the source of the fault is disconnected. If all 5 V reference components have been disconnected and a fault is still indicated, the fault may exist in the wiring harness.