G 2500 3/4 Ton Van V8-350 5.7L VIN K TBI (1995)
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Fused Jumper Wire
A fused jumper is available (J 36169 or equivalent) with small clamp connectors providing adoption to most connectors without damage. This fused
jumper wire is supplied with a 20 amp fuse which may not be suitable for some circuits. Do not use a fuse with a higher rating than the fuse that protects
the circuit being tested.
NOTE: Do not use fused jumper wire in any instance to substitute for inputs or outputs at the Electronic Control Module (ECM). Body Control Module
(BCM), or any microprocessor device.
Short Finder
Short Finders are available (J 8681-A or equivalent) to locate hidden shorts to ground. The short finder creates a pulsing magnetic field in the shorted
circuit and shows you the location of the short through body trim or sheet metal.
Fuse Tester
A simple tester that indicates a blown fuse is available (J 34764 or equivalent). To check a fuse, the tester is applied directly to the fuse in the fuse block.
Two probes contact the fuse. The probes are either placed into the slots of a flat fuse or to the metal ends of a glass fuse. With power "ON", a red LED in
the tester lights if the fuse is open. The handle of the tester is a tool for removing either type of fuse.
Four-Step Troubleshooting Procedure
STEP 1: CHECK THE PROBLEM
Perform a System Check to be sure you understand what's wrong. Don't waste time fixing part of the problem! Do not begin disassembly or testing
until you have narrowed down the possible causes.
If the system you are troubleshooting has a built-in self- diagnostic system, enter diagnostics and check for trouble codes.
STEP 2: READ THE ELECTRICAL SCHEMATIC
Study the schematic. Read the Circuit Operation text if you do not understand how the circuit should work. Check circuits that share wiring with
the problem circuit. The names of circuits that share the same fuse, ground, switch, etc. are included on each electrical schematic. (Shared circuits
are also shown on Power Distribution, Ground Distribution and I/P Fuse Block/Relay Center Details.) Try to operate the shared circuits. If these
circuits work, then the shared wiring is OK. The cause must be within the wiring used only by the problem circuit. If several circuits fail at the
same time, chances are the power (fuse) or ground circuit is faulty.
STEP 3: FIND THE CAUSE AND REPAIR
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Narrow down the possible causes.
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Use the Troubleshooting Hints.
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Make the necessary measurements as given in the System Diagnosis.
Before you replace a component, check power, signal, and ground wires at the component harness connector. If these are OK, the component must
be bad.
STEP 4: TEST THE REPAIR
Repeat the System Check to be sure you have fixed the whole problem.
EXAMPLE: A customer brings in a vehicle and says that the HI beams do not work.
Step 1: Perform System Check on the Headlamps Circuit. You may discover that both LO beams operate. In HI, you may notice that the HI Beam
Indicator comes "ON", but neither beam operates.