Power Supply Relay (TERMINAL 50), Checking

Power Supply Relay (TERMINAL 50), Checking

Observe all safety precautions: => [ Safety Precautions ] Safety Precautions

View clean working conditions: => [ Clean Working Conditions ] Clean Working Conditions

Prior to repair work, perform a preliminary check to verify the condition. Refer to => [ Preliminary Check ] Preliminary Check.

Use only gold-plated terminals when servicing any component with gold-plated electrical harness connector terminals.

For wiring diagrams, component locations, and connector views, Refer to the applicable wiring diagram.

Special tools, testers and auxiliary items required

• Multimeter

• Wiring diagram

Test requirements

• The engine control module fuses OK

• Battery voltage at least 12.5 volts

• All electrical consumers switched off

• Vehicles with automatic transmission, shift selector lever in park or neutral

• A/C switched off

• Ground connections between engine/transmission/chassis OK

• Ignition switched off

Test procedure

- Remove the engine control module power supply relay Power Supply Relay (terminal 50) (J682).

Checking the supply voltage

- Turn the ignition switch ON

- Using a multimeter, measure the voltage of the engine control module power supply relay circuit (socket 1/30).

Specified value: battery voltage.

- Turn the ignition switch OFF

If the specified value was not obtained:

- Check the power supply circuit to the engine control module power supply relay Power Supply Relay (terminal 50) (J682)for an open circuit or a short circuit.

- Check the wiring connections for damage, corrosion, loose or broken terminals.

- Repair as necessary.

- Turn the ignition switch ON

- Using a multimeter, measure the voltage of the engine control module power supply relay ignition circuit (socket 3/86).

Specified value: battery voltage.

- Turn the ignition switch OFF

If the specified value was not obtained:

- Check the ignition circuit to the engine control module power supply relay Power Supply Relay (terminal 50) (J682) for an open circuit or a short circuit.

- Check the wiring connections for damage, corrosion, loose or broken terminals.

Checking wiring

- Remove the engine control module. Refer to the service information for removal and installation procedures.

- Using a multimeter, measure the resistance of the circuit between the power supply relay Power Supply Relay (terminal 50) (J682) and the engine control module Engine Control Module (ECM) (J623). Refer to the applicable wiring diagram.






Specified value: 1.5 ohms Max.

If the specification was not obtained:

- Check the wires for a short circuit to each other, a short to battery voltage, and a short to ground.

- Check the electrical harness connector for damage, corrosion, loose or broken terminals.

- Repair as necessary.

If no malfunction is found in the wiring and voltage supply was OK:

- Replace the engine control module power supply relay Power Supply Relay (terminal 50) (J682).

Final procedures

After repair work, the following work steps must be performed in the following sequence:

1. Check the DTC memory. Refer to => [ Diagnostic Mode 03 - Read DTC Memory ] Diagnostic Modes 01 - 0A.

2. If necessary, erase the DTC memory. Refer to => [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Modes 01 - 0A.

3. If the DTC memory was erased, generate readiness code. Refer to => [ Readiness Code ] Readiness Code.