Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer is having trouble understanding the signals from some sensors because they might not be set up correctly.
This code indicates a problem with the programming or calibration of the supply voltage sensors in the vehicle's control system.
The P189A code is triggered when the vehicle's control module detects an error in the programming or calibration of the supply voltage sensors. This can affect the sensors' ability to provide accurate data to the control module, potentially leading to performance issues.
• Check engine light on
• Erratic engine performance
• Poor fuel economy
• Incorrect sensor programming
• Faulty sensor calibration
• Software update required
OBD-II: On-Board Diagnostics, a system for self-diagnosing and reporting vehicle issues.
ECM: Engine Control Module, the computer that controls engine functions.
• Check for any software updates for the vehicle's control module.
• Inspect the wiring and connections of the supply voltage sensors.
• Verify the calibration and programming of the sensors.
• Reprogram the sensors using the manufacturer's software.
• Update the vehicle's control module software.
• Replace faulty sensors if necessary.
• OBD-II scanner
• Multimeter
• Manufacturer's diagnostic software
$150 - $500
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly update vehicle software.
• Ensure sensors are properly calibrated.
• Perform routine maintenance checks.
Sensor Issue
• Have your vehicle checked by a professional mechanic.
• Avoid driving long distances until the issue is resolved.
Check with your vehicle manufacturer for warranty coverage on sensor issues.
This code has been more common in vehicles with outdated software or after improper sensor replacements.
Moderate – It should be addressed soon to avoid potential performance issues.
Ignoring this code may lead to vehicle performance issues, which could affect safety.
• Vehicle must be running.
• Sensors must be connected and active.
Supply voltage sensors are typically located near the engine or within the engine control module.
Q: Can I drive with a P189A code?
A: It's not recommended to drive for long distances as it may affect vehicle performance.
Q: How do I clear a P189A code?
A: The code can be cleared using an OBD-II scanner, but the underlying issue should be fixed first.
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