Control Relay

System Schematic:

Failure of the control relay could interrupt power supply to the fuel pump, injectors and ECU, resulting in start failure. Also see Fuel Pump and/or Power Circuits in TESTING PROCEDURES.

Test control relay by removing relay and checking the following terminals of the control relay.

Fig. 1 Relay Test:

Caution
Use caution when connecting jumper wires to the relay. If they are incorrectly connected the relay will be damaged.

1. Connect jumper wires between relay terminals 10 and 8 and a 12v power source. Terminal 10 is positive (+) and 8 is negative (-).

2. Measure the voltage at terminals 4 and 5 with the power connected and disconnected at terminal 8.

POWER TO RELAY VOLTAGE READING TERMINALS 4 & 5

On System Voltage
Off 0 Volts

Fig. 2 Relay Test:

3. Connect jumper wires between relay terminals 9 and 6 and a 12v power source. Terminal 9 is positive (+) and 6 is negative (-).

4. Check for continuity at terminals 2 and 3 with the power connected and disconnected at terminal 6.

POWER TO RELAY CONTINUITY READING TERMINALS 2 & 3

On Continuity
Off No Continuity

Fig. 3 Relay Test:

5. Connect jumper wires between relay terminals 3 and 7 and a 12v power source. Terminal 3 is positive (+) and 7 is negative (-).

6. Measure the voltage at terminal 2 with the power connected and disconnected at terminal 7.

POWER TO RELAY VOLTAGE READING TERMINAL 2

On System Voltage
Off 0 Volts

7. Replace the control relay if it fails any of the previous tests.