Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that a sensor in the car that checks the temperature of a part called the starter generator is saying it's too hot.
The code indicates that the temperature reading from the high voltage starter generator sensor is higher than the expected range.
The P1E09 code is triggered when the Powertrain Control Module (PCM) detects a temperature reading from the high voltage starter generator temperature sensor that is above the normal operating range. This could indicate a fault in the sensor, wiring, or the starter generator itself.
• Check Engine Light is on
• Possible reduced vehicle performance
• Unusual noises from the starter generator
• Faulty high voltage starter generator temperature sensor
• Wiring issues such as shorts or open circuits
• Overheating of the starter generator
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Use an OBD-II scanner to confirm the code
• Inspect the wiring and connections to the temperature sensor
• Test the temperature sensor for proper operation
• Replace the high voltage starter generator temperature sensor
• Repair or replace damaged wiring or connectors
• Inspect and repair the starter generator if overheating is confirmed
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $500
Moderate
• Chevrolet Volt
• Chevrolet Malibu Hybrid
• Cadillac ELR
• Regular maintenance checks
• Ensure proper cooling system operation
• Avoid excessive load on the vehicle's electrical system
Sensor Issue
• Do not ignore the Check Engine Light
• Seek professional diagnosis if unsure
• Avoid driving the vehicle if overheating is suspected
Check with the vehicle manufacturer for warranty coverage on hybrid components.
This code is more common in hybrid vehicles due to the complexity of their electrical systems.
Moderate – Should be addressed soon to avoid potential damage to the starter generator.
Ignoring this code may lead to further vehicle damage or reduced performance.
• Vehicle at operating temperature
• Engine running
The high voltage starter generator is typically located near the engine or transmission, depending on the vehicle model.
Q: Can I drive with a P1E09 code?
A: It's not recommended to drive for extended periods with this code, as it may indicate overheating which can cause damage.
Q: How can I reset the P1E09 code?
A: After repairs are made, you can reset the code with an OBD-II scanner. However, if the issue persists, the code will return.
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