Code 28 - Pressure Switch Manifold (PSM): Notes

Fig 1: Pressure Switch Manifold Circuit Diagram

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NOTE: Test numbers refer to numbers on diagnostic chart.

1. This step tests for proper operation of pressure switches.
2. This step tests for correct voltage from PCM/TCM to transmission pass-through connector.
3. This step tests for short to ground in any one of 3 pressure switch circuits.