AutoCodes – Generic – P2798

P2798 Code - Auxiliary Transmission Fluid Pump Control Circuit Low

Quick Answer

The Hybrid Vehicle Control ECU monitors the operation of the Auxiliary Transmission Fluid Pump. Common causes include Faulty Oil Pump Motor Controller, Oil Pump Motor Controller harness is open or shorted, Oil Pump Motor Controller circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P2798 indicates Auxiliary Transmission Fluid Pump Control Circuit Low.
Common causes: Common causes include Faulty Oil Pump Motor Controller, Oil Pump Motor Controller harness is open or shorted, Oil Pump Motor Controller circuit poor electrical connection.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 19,661

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Aug 26, 2021

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P2798 Description

The Hybrid Vehicle Control ECU monitors the operation of the Auxiliary Transmission Fluid Pump. If the Hybrid Vehicle Control ECU detects a malfunction of the Auxiliary Transmission Fluid Pump control circuit, the Hybrid Vehicle Control ECU will illuminate the MIL and set a Diagnostic Trouble Code (DTC).

OBDII Code P2798 - Auxiliary Transmission Fluid Pump Control Circuit Low - AutoCodes.com — P2798 Code - Auxiliary Transmission Fluid Pump Control Circuit Low

What does this mean?

What are the Possible Causes of the DTC P2798?

Faulty Oil Pump Motor Controller
Oil Pump Motor Controller harness is open or shorted
Oil Pump Motor Controller circuit poor electrical connection
Faulty Hybrid Vehicle Control ECU

How to Fix the DTC P2798?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P2798 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the P2798 code?

Need more information on how to fix the P2798 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P2798 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

P2798 Lexus — Auxiliary Transmission Fluid Pump Control Circuit Low
P2798 Toyota — Auxiliary Transmission Fluid Pump Control Circuit Low

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P2798 Code

1. What are the common symptoms of OBDII code P2798?

- Common symptoms include poor transmission performance, difficulty shifting gears, and the illumination of the Check Engine light.

2. What could cause the Auxiliary Transmission Fluid Pump Control Circuit Low code (P2798) to trigger?

- The code can be triggered by issues such as a faulty transmission fluid pump, damaged wiring or connectors in the control circuit, or a low transmission fluid level.

3. How can I diagnose the cause of OBDII code P2798?

- Diagnosis typically involves using a scan tool to read the code, checking the transmission fluid level and condition, inspecting the wiring and connectors related to the auxiliary transmission fluid pump, and testing the pump itself for proper operation.

4. Can a low transmission fluid level cause OBDII code P2798 to appear?

- Yes, a low transmission fluid level can cause insufficient pressure in the system, triggering the P2798 code related to the auxiliary transmission fluid pump control circuit.

5. What are the repair options for OBDII code P2798?

- Repair options may include topping up the transmission fluid, repairing or replacing damaged wiring or connectors, and replacing the auxiliary transmission fluid pump if it is found to be faulty.

6. Is it safe to continue driving with OBDII code P2798 present?

- It is not recommended to continue driving with this code present, as it can lead to further transmission issues and potentially cause more damage over time.

7. Can I reset the Check Engine light after addressing OBDII code P2798 myself?

- Yes, once the underlying issue causing the code has been resolved, the Check Engine light can be reset using an OBDII scan tool to clear the code.

8. How much does it typically cost to repair OBDII code P2798?

- The cost of repairing OBDII code P2798 can vary depending on the specific cause of the issue, but it may range from a few hundred to over a thousand dollars, including parts and labor.

9. Are there any preventive measures to avoid OBDII code P2798 in the future?

- Regularly checking and maintaining the transmission fluid level, conducting routine inspections of the transmission system, and addressing any issues promptly can help prevent the occurrence of code P2798.

10. How long does it take to repair OBDII code P2798?

- The repair time for OBDII code P2798 can vary depending on the cause of the issue and the extent of repairs needed, but it typically takes a few hours to a full day for diagnosis and repair.