Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the car's starter generator, which helps start the engine and generate electricity. It's like when a toy's battery is too strong, and it might cause the toy to act funny.
The P1A79 code indicates that the voltage in the starter generator circuit is higher than expected, which could cause performance issues.
The P1A79 code is triggered when the Powertrain Control Module (PCM) detects a voltage level that is higher than the specified range in the starter generator circuit. This could be due to a malfunctioning component or wiring issue.
• Check Engine Light is on
• Difficulty starting the vehicle
• Reduced fuel efficiency
• Faulty starter generator
• Wiring issues in the starter generator circuit
• Defective Powertrain Control Module (PCM)
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics II
• Use an OBD-II scanner to confirm the code
• Inspect the starter generator and associated wiring for damage
• Test the voltage levels in the circuit
• Replace the faulty starter generator
• Repair or replace damaged wiring
• Reprogram or replace the PCM if necessary
• OBD-II scanner
• Multimeter
• Wrench set
$300 - $800
Moderate
• Chevrolet Volt
• Toyota Prius
• Honda Insight
• Regular maintenance checks
• Ensure proper battery connections
• Avoid overloading the electrical system
Electrical Circuit Issue
• Avoid driving long distances until repaired
• Monitor the vehicle's performance closely
• Consult with a professional mechanic
Check with the vehicle manufacturer for specific warranty coverage related to the starter generator.
The P1A79 code has been associated with hybrid and electric vehicles where the starter generator plays a crucial role in both starting the engine and generating electricity.
Moderate – It is advisable to address this issue soon to avoid potential damage to the vehicle's electrical system.
Ignoring this code may lead to further damage and could affect vehicle safety and emissions compliance.
• Vehicle in 'ON' position
• Engine running
The starter generator is typically located near the engine, connected to the vehicle's electrical system.
Q: Can I drive with a P1A79 code?
A: It's best to address the issue soon, as driving with this code may cause further damage.
Q: What causes a starter generator circuit to be high?
A: Possible causes include a faulty starter generator, wiring issues, or a defective PCM.
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