P2639 OBD-II Trouble Code: Torque Management Feedback Signal A Low

Our certified mechanics come to you · Get a fair and transparent estimate upfront

Red-stars EXCELLENT RATING ON

Cost of diagnosing the P2639 code

P2639 is a diagnostic trouble code (DTC) for "Torque Management Feedback Signal A Low". This can happen for multiple reasons and a mechanic needs to diagnose the specific cause for this code to be triggered in your situation. Our certified mobile mechanics can come to your home or office to perform the Check Engine Light diagnostic for $114.99 . Once we are able to diagnose the problem, you will be provided with an upfront quote for the recommended fix and receive $20.0 off as a credit towards the repair. All our repairs are backed by our 12-month / 12,000-mile warranty.

Cars Estimate Credit towards follow-up repair Earliest Availability
Ford $114.99 $20.0
Toyota $114.99 $20.0
BMW $124.99 $20.0
SCHEDULE P2639 DIAGNOSTIC Get a fair and transparent estimate upfront

P2639 code definition

This DTC indicates Torque Management Feedback Signal A Low.

What the P2639 code means

This code sets when one of the components involved in torque management sends a signal to one of the supporting control modules which falls outside of the expected voltage range. These controllers may include the transmission control module (TCM), the antilock brake control module, the body control module, the fuel injection control module, or a range of other modules which monitor the vehicle’s systems. The letter A refers to a specific area of the involved circuitry.

What causes the P2639 code?

One of the most common culprits in this fault is a driver problem within the PCM or other supporting controller. Another frequent issue is a bad connection in the circuitry. Other possible causes may include:

  • An open or short due to damaged CAN bus (the complex network of harnesses and wires connecting various control modules together) wires or connectors
  • A loose ground strap or damaged ground wire to the involved control module
  • A faulty CAN bus harness

What are the symptoms of the P2639 code?

The Service Engine Soon light may come on, but it may take up to eight drive cycles for this to occur. Other signs could include harsh shifting, poor drivability, engine stalls, rough idling, sluggish acceleration, and/or reduced fuel efficiency. In addition, if the Check Engine light has not illuminated yet, the DTC may show as “pending”.

How does a mechanic diagnose the P2639 code?

Accurate diagnosis of this condition may require:

  • Scanning the vehicle to check for any concurrent codes and to record freeze frame data
  • Clearing the DTCs to see if they return (in an attempt to diagnose an intermittent condition)
  • Using a specialized CAN scanner to detect control module operation and pin values
  • Visually inspecting all involved wiring and connectors to check for damage or loose connections
  • Testing for continuity to the battery ground
  • Testing of the control modules related to the torque management feedback signal

Common mistakes when diagnosing the P2639 code

The most common error in diagnosing this condition is failure to follow the recommended procedure of diagnosing and repairing other DTCs present with the torque converter management signal fault. Transmission or drivability codes that may accompany the controller communication fault include lean exhaust, fuel injector, engine misfire, or other codes.

How serious is the P2639 code?

While this fault may not cause serious fallout, it can impair the way the vehicle runs, potentially causing you to stall out at an inconvenient time. Rough shifting may also occur, affecting drivability, as well as decreased fuel efficiency. It’s best to have this DTC diagnosed and repaired promptly.

What repairs can fix the P2639 code?

Your technician may perform the following repairs:

  • Verifying the set code and any other faults that are present, and recording freeze frame data
  • Clearing the data from the vehicle’s computer to see if the problem returns (otherwise an intermittent condition may exist)
  • Repairing faulty wiring and connections involved in the relevant control modules
  • Repairing any problems in the complex collection of harnesses and connectors which make up the CAN bus network
  • Replacing any faulty control modules

Additional comments for consideration regarding the P2639 code

This diagnosis and repair could involve extensive procedures to find the source of the fault, and often requires specialized equipment like a CAN bus scanner in order to pinpoint problems without painstaking hours of examination. In addition, some vehicle models may contain up to 18 different control modules, making it a challenging undertaking to identify the source of the problem.

For these reasons, it’s often most economical and efficient to leave P2639 repair to a qualified technician.

Need help with a P2639 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

Check Engine Light
trouble codes
P2639

No more waiting rooms! Our mechanics will come to you to diagnose and fix the P2639 code.

SCHEDULE P2639 DIAGNOSTIC
Get a $20 credit for the follow-up repair

Recent Check Engine Light is on Inspection reviews

Excellent Rating

(7400)

Rating Summary
6879
249
58
41
173
6879
249
58
41
173
 at YourMechanic

David

13 years of experience
393 reviews
David
13 years of experience
Chevrolet Malibu L4-2.4L - Check Engine Light is on Inspection - Marietta, Georgia
He explained everything to me in detail on what I needed to know about my car. Definitely recommend him for getting the job done.
 at YourMechanic

Raymond

37 years of experience
402 reviews
Raymond
37 years of experience
Toyota Camry L4-2.2L - Check Engine Light is on - Las Vegas, Nevada
Raymond did a great job however I was charged for two hours labor and he was only here less than 45 minutes. should I expect this on future appointments with your mechanic ?
 at YourMechanic

Shane

17 years of experience
217 reviews
Shane
17 years of experience
Volkswagen EuroVan V6-2.8L - Check Engine Light is on Inspection - Austin, Texas
Arrived on time. Explained the issues he found and how he will fix it. I have parts on order and will schedule an appointment to have Shane install the parts when they arrive.
 at YourMechanic

Kanstantsin

19 years of experience
51 reviews
Kanstantsin
19 years of experience
Ford F-150 V8-4.6L - Check Engine Light is on Inspection - Littleton, Colorado
Kanstantsin arrived early. Was very courteous and professional. Will highly recommend to anyone. Thank you Kanstantsin.


More related articles

P2054 OBD-II Trouble Code: Reductant Injector Circuit Low Bank 1 Unit 2
P2054 P2054 trouble code definition Reductant Injector Circuit Low Bank 1 Unit 2 What the P2054 code means This code indicates a problem with the circuit that controls the reductant injector. The terms “circuit low” refers to a lower than...
P2405 OBD-II Trouble Code: EVAP Leak Detection Pump Control Circuit Low
P2405 code definition Evaporative Emission Control System (EVAP) Leak Detection Pump Control Circuit Low What the P2405 code means P2405 is an OBD-II generic code for the Engine Control Module (ECM) detecting that the evaporative system leak detection...
P0715 OBD-II Trouble Code: Input/Turbine Speed Sensor Circuit Malfunction
P0715 means the transmission will not be able to read the engine RPMs to shift properly causing transmission to shift hard or erratic.

Related questions

ABS signal and Check Engine signal
Hello there. I would need a better description of any symptoms your car is experiencing for more precise advice. There are at least eight sensors on the engine. The camshaft (https://www.yourmechanic.com/services/camshaft-position-sensor-replacement) or crankshaft sensor (https://www.yourmechanic.com/services/crankshaft-position-sensor-replacement) are a couple of the...
Accessory / Ignition Power is inconsistent
Hello there, thank you for asking about your 2004 Nissan 350Z. This is a commonly known issue with the 350Z. You should have a Check Engine Light on when this happens which will be likely related to NATS computer codes....
Egr solenoid
Hi there. Once these parts are replaced you need to do the test procedure with the same plug otherwise the light will remain on. If you did the reset then the circuit will need to be tested. It can also...

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1 (855) 347-2779 · hi@yourmechanic.com