DTC 99, App No. 2 (5-Volt Reference Fault): Notes

Accelerator Pedal Position (APP) module provides a voltage signal that changes relative to accelerator position. There are 3 sensors located within APP module that are scaled differently. DTC 99 will set when reference voltage on APP No. 2 is less than 4.8 volts for 2 seconds. When DTC 99 is set, PCM will light SERVICE THROTTLE SOON light and limit power.

NOTE: Test numbers refer to numbers on diagnostic chart.

This step determines there is a good 5-volt reference.