The P0B04: Auxiliary Transmission Fluid Pump Motor Phase V Current Low fault code indicates that the Phase V current in the auxiliary transmission fluid pump motor is lower than expected. This could be due to a faulty current sensor, issues with wiring or connections, or a malfunction in the auxiliary transmission fluid pump motor itself. Low current can affect the motor’s ability to circulate transmission fluid, which is essential for transmission cooling and lubrication.
P0B04 – Quick Overview
| Code | Information |
|---|---|
| Meaning | P0B04: Auxiliary Transmission Fluid Pump Motor Phase V Current Low |
| Is it serious? | Yes, low Phase V current can affect the motor’s ability to circulate transmission fluid, impacting cooling and lubrication. |
| Possible causes | – Low Phase V current in the auxiliary transmission fluid pump motor – Faulty current sensor – Wiring or connection issue |
| How to diagnose? | – Measure Phase V current to verify low reading – Test the current sensor – Inspect wiring and connections |
P0B04 Meaning
The P0B04: Auxiliary Transmission Fluid Pump Motor Phase V Current Low fault code signals that the Phase V current in the transmission fluid pump motor is lower than normal. This phase is critical for powering the motor that circulates transmission fluid, ensuring the transmission remains cool and properly lubricated. A malfunctioning current sensor, wiring issues, or a faulty motor could lead to inadequate transmission fluid flow, reducing system efficiency.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to check for any related fault codes that might provide additional context on the low Phase V current issue. | OBD-II Scanner |
| Measure Phase V Current | Use a multimeter or diagnostic tool to measure the Phase V current of the auxiliary transmission fluid pump motor. Compare the readings with manufacturer specifications to confirm the low current condition. | Multimeter, Diagnostic Tool |
| Test the Current Sensor | Test the Phase V current sensor to verify its accuracy and proper functioning. A faulty sensor could give inaccurate current readings. | Multimeter, Diagnostic Tool |
| Inspect Wiring and Connections | Inspect the wiring and connections associated with the Phase V current sensor for signs of damage, loose connections, or corrosion. | Flashlight, Multimeter |
| Repair or Replace Components | Repair or replace any faulty components, including the current sensor, wiring, or the transmission fluid pump motor, to restore normal Phase V current levels. | Repair Tools, Replacement Parts |
| Clear the Code and Test Drive | After repairs are made, clear the fault code using an OBD-II scanner and take the vehicle for a test drive to ensure the issue is resolved. | OBD-II Scanner |
| Recheck for Codes | Re-scan the vehicle after the test drive to confirm that the P0B04 code does not return. | OBD-II Scanner |
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