The P0C85: Hybrid Battery Temperature Sensor ‘H’ Circuit Intermittent/Erratic refers to a problem where the signal from the Hybrid Battery Temperature Sensor ‘H’ is unstable, intermittent, or erratic. This can be caused by wiring issues, a faulty temperature sensor, or circuit problems.
P0C85 – Quick Overview
Code | Information |
---|---|
Meaning | P0C85: Hybrid Battery Temperature Sensor ‘H’ Circuit Intermittent/Erratic |
Is it serious? | Yes, erratic temperature readings can cause improper battery management, leading to overheating or reduced system efficiency. |
Possible causes | – Intermittent sensor signal – Faulty temperature sensor – Wiring or circuit issues |
How to diagnose? | – Monitor the sensor signal for intermittency – Test the sensor and circuit – Inspect wiring and connections |
P0C85 Meaning
The P0C85: Hybrid Battery Temperature Sensor ‘H’ Circuit Intermittent/Erratic code indicates that the signal from the Hybrid Battery Temperature Sensor ‘H’ is inconsistent or unstable. This can result in improper temperature readings, which may lead to incorrect hybrid battery management. The issue could stem from a faulty sensor, a problem with the wiring, or an issue with the circuit.
Step-by-step diagnostic guide
Action | Description | Tools Needed |
---|---|---|
Check for Other Codes | Use an OBD-II scanner to check for additional codes that may provide more context for the erratic sensor signal. | OBD-II Scanner |
Monitor Sensor Signal | Use a diagnostic tool or oscilloscope to monitor the signal from Hybrid Battery Temperature Sensor ‘H’ for any signs of intermittency or erratic behavior. | Oscilloscope, Diagnostic Tool |
Test the Temperature Sensor | Test the sensor’s performance under various conditions to ensure it provides consistent and reliable readings. | Multimeter, Temperature Sensor Tester |
Inspect the Sensor Circuit | Visually inspect the sensor circuit for signs of damage, loose connections, or corrosion that could cause intermittent signals. | Flashlight, Multimeter |
Check Wiring and Connections | Inspect the wiring and connectors between the sensor and the control unit for any signs of wear, fraying, or disconnections that may lead to erratic signal transmission. | Flashlight, Multimeter |
Test Circuit Continuity | Perform a continuity test on the sensor circuit to check for any breaks or resistive connections that may cause the intermittent issue. | Multimeter |
Clear the Code and Test Drive | After repairs, clear the P0C85 code using an OBD-II scanner and take the vehicle for a test drive to ensure the issue is resolved. | OBD-II Scanner, Vehicle Owner’s Manual |
Recheck for Codes | After the test drive, re-scan the vehicle to verify that the P0C85 code has not returned. | OBD-II Scanner |

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