AutoCodes – Dodge – P2551 Dodge

P2551 Dodge Code - Torque Management Request Input Signal 'B' High

Quick Answer

To improve shift feel, the Transmission Control Module (TCM) may request that the Engine Control Module (ECM) reduce engine torque during shift events. Common causes include Faulty Engine Control Module (ECM), Faulty Transmission Control Module (TCM), Engine Control Module (ECM) software update. 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: P2551 Dodge indicates Torque Management Request Input Signal 'B' High.
Common causes: Common causes include Faulty Engine Control Module (ECM), Faulty Transmission Control Module (TCM), Engine Control Module (ECM) software update.
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 2,986

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 Jan 18, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P2551 Dodge Description

To improve shift feel, the Transmission Control Module (TCM) may request that the Engine Control Module (ECM) reduce engine torque during shift events. When such a request is received, the ECM responds by retarding the base ignition timing and notifying the TCM that the request has succeeded. If the ECM is unable to comply with the request, the ECM sends the TCM a message that the request has failed.
The torque reduction request is sent to the ECM through a communication network called the controller area network (CAN). Two circuits are used to communicate CAN data between the ECM and TCM.
A fault in the CAN will not cause the ECM to set the Diagnostic Trouble Codes (DTC). If a CAN fault occurs, other DTCs will set before this code.
The ECM set the OBDII code when the TCM receives a torque reduction failure message from the ECM.

OBDII Code P2551 Dodge - Torque Management Request Input Signal 'B' High - AutoCodes.com — P2551 Dodge Code - Torque Management Request Input Signal 'B' High

What does this mean?

What are the Possible Causes of the DTC P2551 Dodge?

Faulty Engine Control Module (ECM)
Faulty Transmission Control Module (TCM)
Engine Control Module (ECM) software update
Transmission Control Module (TCM) software update
Engine Control Module (ECM) harness is open or shorted
Engine Control Module (ECM) circuit poor electrical connection

How to Fix the DTC P2551 Dodge?

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 P2551 Dodge 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.

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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 P2551 Dodge Code

What does the OBDII code P2551 mean on a Dodge vehicle?

1. P2551 indicates that the Torque Management Request Input Signal 'B' is reading higher than expected, signaling a potential electrical or communication issue in the system. 2.

What are the common symptoms of code P2551 in a Dodge?

Symptoms may include reduced engine performance, transmission shifting issues, activation of limp mode, or an illuminated check engine light. 3.

What causes the P2551 code to appear in a Dodge vehicle?

Common causes include a faulty torque management request sensor, damaged wiring or connectors, a malfunctioning throttle body, or a failed powertrain control module (PCM). 4.

How do I diagnose code P2551 on my Dodge?

Start by inspecting the wiring and connectors for damage or corrosion. Use a scan tool to monitor live data for the torque management signal and test the related sensors and circuits for proper function. 5.

Can I drive my Dodge with the P2551 code active?

Driving with the P2551 code is not recommended, as it can lead to poor performance, potential transmission damage, or unsafe driving conditions due to limp mode activation. 6.

How do I fix the P2551 code in a Dodge vehicle?

Repairs may include replacing a faulty sensor, repairing or replacing damaged wiring, cleaning or replacing the throttle body, or reprogramming or replacing the PCM if necessary. 7.

Is the P2551 code specific to Dodge vehicles?

No, the P2551 code can appear in other vehicle makes, but the exact causes and repair procedures may vary depending on the manufacturer. 8.

How much does it cost to repair the P2551 code on a Dodge?

Repair costs depend on the root cause, ranging from $50 for minor wiring repairs to $500 or more for PCM replacement or advanced diagnostics. 9.

Can a weak battery cause the P2551 code in a Dodge?

Yes, a weak or failing battery can cause electrical irregularities that may trigger the P2551 code, so the charging system should be checked during diagnosis. 10.

Do I need a professional mechanic to fix the P2551 code?

If you're experienced with automotive diagnostics, you may resolve simple issues like wiring repairs. However, complex problems, such as PCM replacement or reprogramming, typically require a professional.