Electronic Component Handling and Replacement

Electrical Connections and Circuits
Prior to disconnecting, fully release connector locks.

Ensure connectors are fully seated and all insulators and shields are in place when installed.

Never connect or disconnect electrical connections with the ignition switch ON, unless directed to do so by a test procedure.

Do not test continuity with a self powered test lamp.

Avoid arcing when checking circuit continuity.


TESTING
When measuring voltage at the control unit harness connector disconnect harness connector with the ignition OFF then turn ignition ON as necessary.

To prevent deforming control unit harness connectors do not probe terminals directly. Instead insert a pin from the harness side and perform measurements through pin.


NOTE: Before disconnecting battery ground, access trouble codes and radio presets. Control unit memory is erased when ground is removed.


CONTROL UNIT DAMAGE
Do not try to disassemble the control unit.
Before performing electrical welding disconnect the battery, climate control, injection, cruise control, control unit, and radio.
If temperatures may exceed 80°C (176°F) remove all control units.
Avoid getting water on any fuel and engine control system components.
Never apply battery power to a component unless directed to do so in a test procedure.