Operation CHARM: Car repair manuals for everyone.

Trouble Shooting Guides

NOTICE: When trouble shooting an electrical system, make sure there are no electrical loads ON, except for the circuits or system being tested. This will help prevent false readings and the chance of a dead battery. After the car has been serviced, always visually inspect the battery to be sure the Green Eye is visible in the battery hydrometer.

Before Trouble Shooting
1. Visually inspect the wires and connectors.
2. Verify that terminal pins are clean and that there are no loose pins or terminals.
3. Verify that the Weather-Pack connectors are in good condition and sealed properly.
4. Check the minifuse, maxifuse or circuit breaker used to protect the circuit or system being tested.
5. Check the battery for damage, state of charge, and for clean and tight connections.
6. Check the accessory drive belt.

Five-step Trouble Shooting
1. Verify the complaint.
^ Perform the System Performance Test, if the section has one, outlined at the beginning of each section. Do not fix only part of the problem. Do not begin disassembly or testing until you have narrowed down the possible causes.
2. Consult the Cause-To-Complaint Charts and analyze the electrical schematic for the system being tested.
^ Use the Cause-To-Complaint Chart, to find the possible cause of the problem.
^ Look at the electrical schematic for the problem circuit. Determine how the circuit is supposed to work and look for minifuses maxifuses, circuit breakers, wires and ground shared with other systems or components. See if a shared wired is at fault by checking the other components fed by the wire.
^ Based on the symptoms and your understanding of the circuit operation, identify one or more possible causes of the problem.
3. Isolate the problem by testing the circuit. Use diagnostic service probes as needed on 18, 20, and 22 gage wires.
^ Perform circuit tests to check the diagnosis made in step two. You can either test for the most likely cause of failure first, or perform the tests which are most easily and quickly done.
^ Generally, fuses and grounds are easiest to check.
4. Fix the problem.
^ Once the problem is identified, make the repair. Make sure to use the proper tools and safe methods mentioned.
5. Make sure the circuit works.
^ Turn on all components in the repaired circuit in all modes of operation. Make sure no new problems have come up and that the original problem has been fixed.