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P1AA9 GMC Code - Starter/Generator Phase U Current Sensor Performance

- Code Popularity: 692 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 3/3
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What are the Possible Causes of the DTC P1AA9 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 Starter/Generator Control Module (SGCM)
  • Starter/Generator Control Module (SGCM) harness is open or shorted
  • Starter/Generator Control Module (SGCM) circuit poor electrical connection
⚠ Does your GMC have Safety Recalls? → Check here

How to Fix the DTC P1AA9 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.

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What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P1AA9 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 P1AA9 GMC Description

The Starter/Generator Control Module (SGCM) unit is an electronic device that works in conjunction with the electrical subsystem to efficiently perform DC/DC and DC/AC electrical energy conversion and support vehicle functions.
This SGCM will have 2 functions. The first will be monitoring, where the DC voltage is transformed into three phase A/C power to the Starter Generator interface. In this case, energy flows from battery 36-volt to Phase 1, Phase 2, Phase 3. The second case will be generating, where the three phase AC power is used to charge the 36 V battery pack. In this case, energy flows from Phase 1, Phase 2, Phase 3 to battery 36-volt. If the values of Starter Generator Speed and Starter Generator Torque are zero, then the Starter Generator Control will be disabled and the Starter Generator Inverter is not transferring or consuming any power.

OBDII Code P1AA9 GMC - Starter/Generator Phase U Current Sensor Performance - AutoCodes.com
P1AA9 GMC Code - Starter/Generator Phase U Current Sensor Performance

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Code P1AA9 GMC comments

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