DTC 62 - Turbo Boost Sensor CKT Low: Notes

WARNING: This page does not describe the selected car, but rather 10 other vehicles, including the 1994 GMC Yukon, 1994 GMC Suburban, 1994 GMC Pickup, 1994 GMC Cab & Chassis, and 1994 GMC C3500 HD. However, it is still accessible from the selected car via links, so may be relevant.

The PCM sends a 5-volt reference signal to the boost sensor. As manifold pressure changes, the electrical resistance of the boost sensor also changes. By monitoring the sensor output voltage, PCM detects how much pressure is being produced by the turbocharger in the intake manifold. The PCM uses the boost sensor to control turbo boost and fuel at different loads. DTC 62 will set when boost signal voltage is less than .8 volt. PCM will default to no turbo boost and limited fuel.

NOTE: Test numbers refer to numbers on diagnostic chart.

This step determines if DTC 62 is the result of a hard failure or an intermittent condition.
This step simulates conditions for DTC 61. If the PCM recognizes the change, then the PCM, and the 5-volt reference circuit and the boost signal circuit are okay.