Crank Relay Functional Test

Diagnostic Chart (Part 1 Of 2):

Diagnostic Chart (Part 2 Of 2):

Refer to Engine Controls Schematic Power, Ground, MIL, DLC, Transaxle Range Sw. Electrical Diagrams
Refer to Starting and Charging, Starter Schematics in Starting and Charging. Starting and Charging

CIRCUIT DESCRIPTION
The Ignition Switch provides ignition positive voltage to the PCM while in the Crank position. When the PCM receives the Crank signal, it then determines if the Theft Deterrent Fuel Enable Signal is correct and received in time. If the signal is accepted then the PCM provides a ground path for the Crank Relay Control Circuit, which closes the Crank Relay contacts and provides battery positive voltage to the Starter Solenoid.

The PCM has the ability to disable the Crank Relay if a short to ignition or battery positive voltage is evident on the Crank Signal circuit, or if the Ignition Switch is left in the crank position for an extended period of time (approximately 5-8 seconds) with the engine running. The Crank Relay will also be disabled if the engine is running, a correct theft deterrent password is not received or if the vehicle is started while not in Park/Neutral position.

The PCM controlled starter system consists of the following components:
- The Ignition Switch
- The Crank Signal
- The PCM
- The Crank Relay Control Circuit
- The Transaxle Range/Park Neutral Position Switch
- The Crank Relay
- The Starter Solenoid
- The Starter Motor

DIAGNOSTIC AIDS
The Crank Relay Functional test is intended to identify electrical malfunctions that can occur with the PCM Control Starter System. For additional system diagnosis, refer to A Diagnostic System Check - Starting and Charging in Starting and Charging.

Inspect for the following conditions:

IMPORTANT: Remove any debris from the connector surfaces before servicing a component. Inspect the connector gaskets when diagnosing or replacing a component. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion.

- Poor terminal connection-Inspect the harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and faulty terminal to wire connection. Use a corresponding mating terminal to test for proper tension. Refer to Diagrams.
- Damaged harness-Inspect the wiring harness for damage. If the harness inspection does not reveal a problem, observe the display on the scan tool while moving connectors and wiring harnesses related to the sensor. A change in the scan tool display may indicate the location of the fault. Refer to Diagrams.
- PCM and engine grounds for clean and secure connections

If the DTC is determined to be intermittent, reviewing the Failure Records can be useful in determining when the DTC was last set.

TEST DESCRIPTION
Numbers below refer to step numbers in the diagnostic table:

IMPORTANT: The Starter is capable of engaging with the ignition OFF, or while in gear.

3. This test determines if the Starter is cranking with the ignition OFF.
4. If the Crank Signal circuit is shorted to battery or ignition positive voltage and the ignition is on the Crank Relay will be commanded ON at ignition power up, and will be disabled after the engine is running.