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 part of the car that helps keep the battery cool. It's like when a fan in your computer stops working, and the computer gets too hot.
The P1B35 code indicates that the electrical circuit controlling the valve that directs coolant to the heat exchanger is experiencing low voltage or a malfunction.
The P1B35 code is set when the Powertrain Control Module (PCM) detects a low voltage condition in the circuit that controls the hybrid or electric vehicle battery coolant valve to the heat exchanger. This valve is crucial for regulating the temperature of the battery by allowing coolant to pass through the heat exchanger.
• Check Engine Light illuminated
• Reduced battery performance
• Overheating of the battery
• Faulty battery coolant valve
• Wiring issues such as shorts or opens in the circuit
• Malfunctioning PCM or control module
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the battery coolant valve for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the faulty battery coolant valve.
• Reprogram or replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$200 - $600
Moderate
• Chevrolet Volt
• Nissan Leaf
• Toyota Prius
• Regular maintenance checks of the cooling system
• Ensure proper electrical connections
• Monitor battery temperature regularly
Sensor Issue
• Avoid driving the vehicle until repaired to prevent battery damage.
• Consult a professional mechanic for accurate diagnosis and repair.
Check with the vehicle manufacturer for warranty coverage on hybrid/EV components.
This code is relatively new and primarily associated with modern hybrid and electric vehicles as they rely heavily on battery temperature management.
High – Immediate attention is required to prevent potential battery damage.
Ignoring this code may lead to battery overheating, which can be a safety hazard.
• Vehicle must be in a safe environment for testing.
• Ensure the battery is at operational temperature.
The battery coolant valve is typically located near the battery pack in hybrid or electric vehicles.
Q: What happens if I ignore this code?
A: Ignoring this code can lead to battery overheating, reduced performance, and potential damage.
Q: Can I drive my car with this code?
A: It's not recommended to drive the car with this code active, as it can cause further damage to the battery.
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