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B1370 GMC Code - Control Module Ignition ON and Start Circuit

- Code Popularity: 8,477 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 3/3
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What are the Possible Causes of the DTC B1370 GMC?

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
  • Faulty Ignition Switch
  • Ignition Switch harness is open or shorted
  • Ignition Switch circuit poor electrical connection
  • Faulty Body Control Module (BCM)
  • Faulty Instrument Cluster (If code is stored in Instrument Cluster)
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How to Fix the DTC B1370 GMC?

Review the 'Possible Causes' mentioned above and visually examine the corresponding wiring harness and connectors. Ensure to check for any damaged components and inspect the connector pins for signs of being broken, bent, pushed out, or corroded.

Code Tech Notes

B1370:01 Control Module Ignition ON and Start Circuit Short to Battery
B1370:04 Control Module Ignition ON and Start Circuit Short to Ground or Open

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What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the B1370 GMC code, it typically requires 1.0 hour of labor. The specific diagnosis time and labor rates at auto repair shops can differ based on factors such as the location, make and model of the vehicle, and even the engine type. It is common for most auto repair shops to charge between $75 and $150 per hour.

What are Code Possible Symptoms?

  • Engine Light ON (or Service Engine Soon Warning Light)

Code B1370 GMC Description

The vehicle Power Mode Master (PMM) is the Body Control Module (BCM). The ignition switch is a low-current switch with multiple discrete circuits to the BCM. The BCM logic uses the ignition switch positions to identify the operator's desired power mode and activate specific discrete signals, and serial data messages for the operation of different subsystems as necessary. Other modules which have switched voltage inputs may operate in a default mode if the Power Mode Master serial data message does not match what the individual module can detect from its own connections.
The Power Mode Master will activate relays and other direct outputs of the Power Mode Master as needed according to the calculated power mode. Some relays controlled by the BCM are switched ignition voltage outputs that are pass-through circuits within the BCM directly from the ignition switch. If these circuits are short to ground, the B+ circuit fuse to the ignition switch will open.

OBDII Code B1370 GMC - Control Module Ignition ON and Start Circuit - AutoCodes.com
B1370 GMC Code - Control Module Ignition ON and Start Circuit

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Code B1370 GMC comments

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