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 the car's computer is confused about which control unit to use. It's like when you can't decide which remote to use for the TV.
The car's computer system is having trouble determining which control unit to select for a particular function.
P1564 indicates that there is a plausibility issue with the control unit selection. This means that the vehicle's main computer (ECU) is receiving conflicting information about which control unit to use for a specific operation. This can be due to a communication error or a fault in one of the control units.
• Check Engine Light is on
• Erratic vehicle behavior
• Loss of certain vehicle functions
• Faulty control unit
• Wiring issues
• Software glitch in the ECU
ECU: Engine Control Unit, the computer that controls engine functions.
OBD-II: On-Board Diagnostics, a standardized system for vehicle diagnostics.
• Use an OBD-II scanner to confirm the code.
• Inspect wiring and connections to the control units.
• Check for software updates for the ECU.
• Reset the ECU and clear the code.
• Repair or replace faulty wiring.
• Update or reprogram the ECU software.
• OBD-II scanner
• Multimeter
• Diagnostic software
$100 - $500
Moderate
• Nissan Altima
• Ford Focus
• Toyota Camry
• Regularly update ECU software.
• Perform routine checks on wiring.
• Avoid aftermarket modifications that affect the ECU.
Control Unit Communication Issue
• Have a professional diagnose the issue.
• Avoid driving the vehicle until the issue is resolved.
Check with your dealer; control unit issues may be covered under powertrain warranty.
This code has been more prevalent in vehicles with complex electronic systems, especially as cars have become more reliant on multiple control units.
Moderate – Should be addressed soon to avoid further complications.
Driving with this code may lead to reduced vehicle performance and should be addressed to ensure safety.
• Vehicle must be running.
• All electrical systems should be operational.
The control units are typically located under the dashboard or in the engine compartment.
Q: Can I drive with a P1564 code?
A: It's not recommended as it may lead to erratic vehicle behavior.
Q: Will resetting the ECU fix the problem?
A: Resetting may clear the code temporarily, but the underlying issue should be diagnosed and repaired.
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