Drive Motor Performance
Table of contents
P0A90 BUICK Possible Causes
- Inspect the drive belt for cracks, wear and contamination
- Faulty Starter Generator
- Starter Generator harness is open or shorted
- Starter Generator circuit poor electrical connection
How do I fix code P0A90 BUICK?
Check the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector’s pins.
Cost of diagnosing the P0A90 BUICK code
The cost of diagnosing the P0A90 BUICK code is 1.0 hour of labor. The auto repair labor rates vary by location, your vehicle’s make and model, and even your engine type. Most auto repairs shops charge between $75 and $150 per hour.
Possible Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
P0A90 BUICK Description
The generator control module also called the starter generator control module is comprised of the following three control modules; the hybrid powertrain control module, 14 volt power module and the drive motor control module. These three control modules are non serviceable and are part of the generator control module.
The eAssist hybrid system has a starter generator also called a drive motor. The starter generator is mounted to the front of the engine and is mechanically connected to the crankshaft pulley by a serpentine belt.
The hybrid powertrain control module receives an engine RPM signal over serial data and compares that value to the starter generator rpm received from the drive motor control module. The hybrid powertrain control module uses a ratio of these two speeds to determine if the drive belt is missing or slipping.