Pinpoint Test A: The Engine Does Not Crank
Starting System
Pinpoint Tests
Pinpoint Test A: The Engine Does Not Crank
Refer to Wiring Diagram Set 20, Starting System for schematic and connector information. Diagrams By Number
Normal Operation
Under normal operation, the Battery Junction Box (BJB) supplies constant power to the starter motor relay on circuit 30-BB12 (RD) through fuse 11 (30A). When the key is placed in the START position with the vehicle in PARK or NEUTRAL, the Transmission Range (TR) sensor provides power on circuit 31S-BB16 (BK/RD) and the PCM provides ground on circuit 31-BB16 (BK). The coil of the relay is energized and sends power to the starter motor on circuit 50-BB12 (GY). The solenoid is grounded at the starter motor. Energizing the starter solenoid will engage the starter drive into the flexplate ring gear and closes the solenoid contacts, allowing power directly from the battery through circuit 30-BB10 (RD) to the starter motor to start the engine.
This pinpoint test is intended to diagnose the following:
- Battery
- Starter motor
- Starter motor relay
- Start diode
- Circuit
- PCM
- TR sensor
PINPOINT TEST A: THE ENGINE DOES NOT CRANK
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A1 CHECK THE BATTERY
- Check the battery condition and state of charge. Refer to Diagnosis and Testing in Battery. Testing and Inspection
- Is the battery OK?
Yes
GO to A2.
No
CHARGE or INSTALL a new battery as necessary. REFER to Battery. TEST the system for normal operation.
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A2 CHECK FOR PCM DTCs
- Using the DTCs retrieved in Inspection and Verification, check for PCM DTCs.
- Were any PCM DTCs retrieved?
Yes
If PCM DTC P1260:00 is retrieved, REFER to Antitheft and Alarm Systems. All other PCM DTCs, REFER to Computers and Control Systems Information.
No
GO to A3.
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A3 CHECK THE PCM AUTOMATIC TR SENSOR PID
- Connect the scan tool.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: DataLogger - PCM.
- While observing the TR sensor PID, place the vehicle in PARK and NEUTRAL.
- Does the PID match the gear selection?
Yes
GO to A4.
No
REFER to Automatic Transmission/Transaxle &/or Transmission Control Systems to diagnose the TR sensor alignment.
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A4 CHECK THE STARTER MOTOR CONTROL OUTPUT DETECTED (SMC_MON) PID
- Enter the following diagnostic mode on the scan tool: DataLogger - PCM.
- Monitor the SMC_MON PID with the ignition switch in the START position.
- Does the PID change from OFF to ON?
Yes
GO to A5.
No
GO to A12.
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A5 CHECK THE STARTER MOTOR RELAY ENABLE (STRT_RLY) PID
- Enter the following diagnostic mode on the scan tool: DataLogger - PCM.
- Monitor the STRT_RLY PID with the ignition switch in the START position.
- Does the PID change from DISABLED to ENABLED?
Yes
GO to A6.
No
GO to A24.
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A6 CHECK FOR VOLTAGE TO THE STARTER MOTOR RELAY
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
- Ignition OFF.
- Disconnect: Starter Motor Relay.
- Measure the voltage between BJB starter motor relay pin 3, circuit 30-BB12 (RD), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to A7.
No
VERIFY BJB fuse 11 (30 A) is OK. If OK, REPAIR the circuit 30-BB12 (RD). TEST the system for normal operation. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. Diagrams By Number
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A7 CHECK THE BATTERY GROUND CABLE
- Measure the voltage between the positive battery post and the battery ground cable connection at the engine.
- Is the voltage greater than 10 volts?
Yes
GO to A8.
No
INSTALL a new battery ground cable. REFER to Battery. TEST the system for normal operation.
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A8 CHECK THE STARTER MOTOR GROUND
- Measure the voltage between the positive battery post and the starter motor case.
- Is the voltage greater than 10 volts?
Yes
GO to A9.
No
CLEAN the starter motor mounting flange and MAKE SURE the starter motor is correctly mounted. TEST the system for normal operation.
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A9 CHECK THE POWER SUPPLY TO THE STARTER MOTOR
- Measure the voltage between starter motor C197A-1, circuit 30-BB10 (RD) and ground.
- Is the voltage greater than 10 volts?
Yes
GO to A10.
No
INSTALL a new positive battery cable. REFER to Battery. TEST the system for normal operation.
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A10 CHECK THE STARTER MOTOR B-PIN
- Connect one end of a fused jumper wire to starter motor solenoid C197A-1, circuit 30-BB10 (RD). Momentarily connect the other end of the jumper to starter motor C197B-1, circuit 50-BB12 (GY).
- Did the starter motor engage and the engine crank?
Yes
GO to A11.
No
INSTALL a new starter motor. REFER to Starter Motor Service and Repair. TEST the system for normal operation.
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A11 CHECK THE CIRCUIT TO THE STARTER MOTOR
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
- Ignition OFF.
- Disconnect: Starter Motor Solenoid C197B.
- Disconnect: Starter Motor Relay.
- Measure the resistance between starter motor solenoid C197B-1, circuit 50-BB12 (GY), harness side and BJB starter relay pin 5, circuit 50-BB12 (GY), harness side.
- Is the resistance less than 5 ohms?
Yes
INSTALL a new starter motor relay. TEST the system for normal operation.
No
REPAIR the circuit 50-BB12 (GY). TEST the system for normal operation.
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A12 CHECK FOR VOLTAGE TO THE STARTER MOTOR RELAY
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
- Ignition OFF.
- Disconnect: Starter Motor Relay.
- Measure the voltage between BJB starter motor relay pin 3, circuit 30-BB12 (RD), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to A13.
No
VERIFY BJB fuse 11 (30 A) is OK. If OK, REPAIR the circuit 30-BB12 (RD). TEST the system for normal operation. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. Diagrams By Number
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A13 CHECK THE STARTER MOTOR RELAY
- Carry out the Starter Motor Relay Component Test.
- Did the starter motor relay pass the component test?
Yes
GO to A14.
No
INSTALL a new starter motor relay. TEST the system for normal operation.
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A14 CHECK CIRCUIT 31S-BB16 (BK/RD) FOR VOLTAGE
- Measure the voltage between BJB starter motor relay pin 1, circuit 31S-BB16 (BK/RD), harness side and ground with the ignition switch in the START position.
- Is the voltage greater than 10 volts?
Yes
GO to A21.
No
GO to A15.
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A15 CHECK THE START DIODE
- Disconnect: Start Diode.
- Check the start diode for an open or shorted condition.
- Is the start diode OK?
Yes
GO to A16.
No
INSTALL a new start diode. TEST the system for normal operation.
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A16 CHECK FOR VOLTAGE AT THE START DIODE
- Measure the voltage between start diode cell, circuit 50-BB16 (GY/BK), harness side and ground with the ignition switch in the START position.
- Is the voltage greater than 10 volts?
Yes
GO to A19.
No
GO to A17.
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A17 CHECK CIRCUIT 30-BB9 (RD) FOR VOLTAGE
- Disconnect: Ignition Switch C250.
- Measure the voltage between ignition switch C250-4, circuit 30-BB9 (RD), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to A18.
No
VERIFY BJB fuse 3 (20 A) is OK. If OK, REPAIR circuit 30-BB9 (RD). TEST the system for normal operation. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. Diagrams By Number
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A18 CHECK THE IGNITION SWITCH
- Carry out the Ignition Switch Component Test.
- Did the ignition switch pass the component test?
Yes
REPAIR circuit 50-BB16 (GY/BK). TEST the system for normal operation.
No
INSTALL a new ignition switch. REFER to Steering Column. TEST the system for normal operation.
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A19 CHECK CIRCUIT 50-BB15A (GY/OG) TO THE TR SENSOR FOR AN OPEN
- Ignition OFF.
- Disconnect: TR Sensor C167.
- Disconnect: PCM C175B.
- Measure the resistance between BJB start diode cell, circuit 50-BB1 (GY/RD), harness side and TR sensor C167-6, circuit 50-BB15 (GY/OG), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to A20.
No
REPAIR the circuit 50-BB1 (GY/RD) or 50-BB15 (GY/OG). TEST the system for normal operation.
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A20 CHECK CIRCUIT 31S-BB16 (BK/RD) FROM THE TR SENSOR TO THE STARTER MOTOR RELAY FOR AN OPEN
- Measure the resistance between BJB starter motor relay pin 1, circuit 31S-BB16 (BK/RD), harness side and TR sensor C167-9, circuit 31S-BB16 (BK/RD), harness side.
- Is the resistance less than 5 ohms?
Yes
INSTALL a new TR sensor. REFER to Automatic Transmission/Transaxle &/or Transmission Control Systems.
No
REPAIR the circuit 31S-BB16 (BK/RD). TEST the system for normal operation.
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A21 CHECK CIRCUIT 50-BB15 (GY/OG) FOR AN OPEN
- Disconnect: Start Diode.
- Disconnect: PCM C175B.
- Disconnect: TR Sensor C167.
- Measure the resistance between BJB start diode cell, circuit 50-BB1 (GY/RD), harness side and PCM C175B-37, circuit 50-BB15A (GY/OG), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to A22.
No
REPAIR the circuit 50-BB1 (GY/RD) or 50-BB15A (GY/OG). TEST the system for normal operation.
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A22 CHECK CIRCUIT 50-BB14 (GY/RD) FOR AN OPEN
- Connect: TR Sensor C167.
- Disconnect: Ignition Switch C250.
- Measure the resistance between BJB start diode cell, circuit 50-BB16 (GY/BK), harness side and PCM C175B-16, circuit 50-BB14 (GY/RD), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to A23.
No
REPAIR the circuit 50-BB14 (GY/RD). TEST the system for normal operation.
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A23 CHECK THE CIRCUIT 31-BB16 (BK) FOR AN OPEN
- Connect: Start Diode.
- Disconnect: Starter Motor Relay.
- Measure the resistance between the BJB starter motor relay pin 2, circuit 31-BB16 (BK), harness side and C175B-7, circuit 31-BB16 (BK), harness side.
- Is the resistance less than 5 ohms?
Yes
INSTALL a new PCM. REFER to Computers and Control Systems. TEST the system for normal operation.
No
REPAIR circuit 31-BB16 (BK). TEST the system for normal operation.
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A24 CHECK FOR VOLTAGE TO THE STARTER MOTOR RELAY
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
- Ignition OFF.
- Disconnect: Starter Motor Relay.
- Measure the voltage between BJB starter motor relay pin 3, circuit 30-BB12 (RD), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to A25.
No
VERIFY BJB fuse 11 (30 A) is OK. If OK, REPAIR the circuit 30-BB12 (RD). TEST the system for normal operation. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. Diagrams By Number
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A25 CHECK THE STARTER MOTOR RELAY
- Carry out the Starter Motor Relay Component Test.
- Did the starter motor relay pass the component test?
Yes
GO to A26.
No
INSTALL a new starter motor relay. TEST the system for normal operation.
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A26 CHECK CIRCUIT 31-BB16 (BK) FOR AN OPEN
- Ignition OFF.
- Disconnect: PCM C175B.
- Disconnect: Starter Motor Relay.
- Measure the resistance between the BJB starter motor relay pin 2, circuit 31-BB16 (BK), harness side and PCM C175B-7, circuit 31-BB16 (BK), harness side.
- Is the resistance less than 5 ohms?
Yes
INSTALL a new PCM. REFER to Computers and Control Systems. TEST the system for normal operation.
No
REPAIR circuit 31-BB16 (BK). TEST the system for normal operation.
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