Chart A-2 Loss of CPS 12 Volts

Chart A-2 - Loss Of CPS 12 Volts:

Wiring Diagram for Chart A-2 - Loss Of CPS 12 Volts:

CHART A-2 - LOSS OF CPS 12 VOLTS


Test Description:

1. Since both the "Service Engine Soon" telltale and the CRT would not illuminate, 12 volts is not leaving the CPS. By checking the CPS fuse first a determination can be made as to whether the problem is a short to ground or opens in the feed circuits to the CPS.

2. Trying another fuse, in the case of a blown fuse, will help you determine if the short to ground is intermittent.


3. Sequentially checking the resistance to ground on each of the CPS's 12 volt circuits will verify the integrity of each branch of the circuit and its components. If circuits check OK, the CPS is faulty.


4. Checking the CPS's feed circuits at the CPS will determine if the circuits are both open or if the CPS connector or CPS is faulty.