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 having trouble talking to the transmission, which is like the car's brain not being able to tell the gears what to do.
The P0898 code indicates a problem with the circuit that requests the Malfunction Indicator Light (MIL) for the transmission control system. This could mean low voltage or a poor connection.
The Transmission Control Module (TCM) monitors the MIL request circuit to ensure proper communication with the Engine Control Module (ECM). A 'low' signal indicates that the circuit is not receiving the expected voltage, which could be due to wiring issues, a faulty TCM, or a bad connection.
• Check Engine Light is on
• Transmission may not shift properly
• Reduced fuel efficiency
• Faulty Transmission Control Module (TCM)
• Poor electrical connection in the MIL request circuit
• Damaged wiring or connectors
MIL: Malfunction Indicator Light
TCM: Transmission Control Module
ECM: Engine Control Module
• Use an OBD-II scanner to confirm the P0898 code.
• Inspect the wiring and connectors in the MIL request circuit for damage.
• Test the voltage levels in the circuit to ensure they meet specifications.
• Repair or replace damaged wiring and connectors.
• Replace the Transmission Control Module if faulty.
• Ensure all connections are secure and free from corrosion.
• OBD-II Scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly inspect and maintain wiring harnesses.
• Keep electrical connections clean and secure.
• Perform routine diagnostic checks.
Transmission Control System Issue
• If you experience shifting problems, have your vehicle inspected promptly.
• Avoid driving aggressively until the issue is resolved.
Check with your vehicle manufacturer for warranty coverage on transmission components.
This code has been associated with communication issues between the TCM and ECM, often due to wiring problems.
Moderate – While the vehicle may still be drivable, addressing this issue promptly can prevent further transmission damage.
Ignoring transmission issues can lead to safety hazards and increased repair costs.
• Vehicle in park or neutral
• Engine running
The Transmission Control Module is usually located under the hood or beneath the dashboard.
Q: Can I drive with a P0898 code?
A: It's possible, but not recommended due to potential transmission issues.
Q: Will clearing the code fix the problem?
A: Clearing the code may turn off the Check Engine Light temporarily, but it won't fix the underlying issue.
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