The P085A: Gear Shift Control Module ‘B’ Communication Circuit refers to a communication issue between the vehicle’s systems and gear shift control module ‘B’. This can be caused by faulty wiring, connector problems, or a malfunction in gear shift control module ‘B’ itself. Proper communication between modules is essential for the vehicle to operate correctly and for the transmission to shift smoothly.
P085A – Quick Overview
Code | Information |
---|---|
Meaning | P085A: Gear Shift Control Module ‘B’ Communication Circuit |
Is it serious? | Yes, this can cause shifting problems and impact overall transmission performance. |
Possible causes | – Communication issues with gear shift control module ‘B’ – Faulty gear shift control module ‘B’ – Wiring or connector issues |
How to diagnose? | – Check communication with gear shift control module ‘B’ – Inspect wiring and connectors – Replace faulty components if needed |
P085A Meaning
The P085A: Gear Shift Control Module ‘B’ Communication Circuit code indicates that there is a failure in communication between the vehicle’s systems and gear shift control module ‘B’. This communication is essential for proper shifting and operation of the transmission, and an issue in this circuit can lead to transmission malfunctions.
Step-by-step diagnostic guide
Action | Description | Tools Needed |
---|---|---|
Check for Other Codes | Use an OBD-II scanner to check for additional related codes that might provide further insights into communication or transmission issues. | OBD-II Scanner |
Inspect Gear Shift Control Module | Visually inspect gear shift control module ‘B’ for signs of damage, misalignment, or loose connections. | Flashlight, Safety Gloves |
Test Communication with Module | Use a diagnostic tool to check for proper communication between gear shift control module ‘B’ and the vehicle’s control systems. | Diagnostic Tool |
Check Wiring and Connectors | Inspect the wiring and connectors for damage, corrosion, or loose connections that could disrupt communication. | Flashlight, Multimeter |
Replace Faulty Components | If gear shift control module ‘B’, wiring, or connectors are faulty, replace the necessary components. | Replacement Parts, Basic Tools |
Clear the Code and Test Drive | After repairs, clear the code using an OBD-II scanner and test the vehicle to ensure proper gear shift communication and performance. | OBD-II Scanner, Vehicle Owner’s Manual |
Recheck for Codes | After the test drive, re-scan the system to confirm that the P085A code does not return. | OBD-II Scanner |

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