AutoCodes – Generic – P1D99

P1D99 Code - Incorrect Gear Ratio Clutch 'B' Or 'E' Defective

Quick Answer

The Transmission Control Module (TCM) monitors for conditions which lead to an unexpected transmission gear ratio (e.g. Common causes include Faulty Transmission Internal Components. 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: P1D99 indicates Incorrect Gear Ratio Clutch 'B' Or 'E' Defective.
Common causes: Common causes include Faulty Transmission Internal Components.
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 9,609

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 Apr 19, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P1D99 Description

The Transmission Control Module (TCM) monitors for conditions which lead to an unexpected transmission gear ratio (e.g. slipping clutches, hydraulic or mechanical defects, etc.). The TCM compares the actual gear ratio (i.e. the ratio of input speed to output speed) to a minimum and maximum calibrated gear ratio value. The TCM performs this comparison while driving in a fixed gear, during gear engagement, and during shifting from one gear to another.

OBDII Code P1D99 - Incorrect Gear Ratio Clutch 'B' Or 'E' Defective - AutoCodes.com — P1D99 Code - Incorrect Gear Ratio Clutch 'B' Or 'E' Defective

What does this mean?

What are the Possible Causes of the DTC P1D99?

Faulty Transmission Internal Components

How to Fix the DTC P1D99?

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 P1D99 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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Need more information on how to fix the P1D99 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1D99 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

P1D99 Acura — Electric Powertrain Coolant Pump Control Circuit Open
P1D99 Chrysler — Incorrect Gear Ratio Clutch 'B' Or 'E' Defective
P1D99 Dodge — Incorrect Gear Ratio Clutch 'B' Or 'E' Defective
P1D99 Fiat — Incorrect Gear Ratio Clutch 'B' Or 'E' Defective
P1D99 Honda — Electric Powertrain Coolant Pump Control Circuit Open
P1D99 Jeep — Incorrect Gear Ratio Clutch 'B' Or 'E' Defective

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 P1D99 Code

1. What are the common symptoms of OBDII code P1D99 (Incorrect Gear Ratio Clutch 'B' Or 'E' Defective)?

- Common symptoms include erratic shifting, transmission slipping, poor acceleration, and illuminated check engine light.

2. What are the possible causes of OBDII code P1D99?

- The code P1D99 can be triggered by a defective clutch 'B' or 'E', low transmission fluid levels, faulty transmission solenoids, or internal transmission damage.

3. How serious is OBDII code P1D99 (Incorrect Gear Ratio Clutch 'B' Or 'E' Defective)?

- This code should be addressed promptly as it can lead to further damage to the transmission if left unresolved, potentially resulting in costly repairs.

4. Can I continue driving my vehicle with OBDII code P1D99?

- It is not recommended to continue driving the vehicle with code P1D99 as it may cause further damage to the transmission and compromise driving safety.

5. How can I diagnose OBDII code P1D99?

- Diagnosis typically involves using a diagnostic scanner to retrieve the code, checking transmission fluid levels, inspecting the clutch 'B' and 'E' components, and performing a thorough transmission system inspection.

6. What are some repair tips for fixing OBDII code P1D99?

- Repair tips may include replacing the defective clutch 'B' or 'E', topping up or replacing transmission fluid, repairing or replacing faulty solenoids, and addressing any other underlying transmission issues.

7. Is it possible to reset OBDII code P1D99 without fixing the underlying issue?

- While clearing the code temporarily may turn off the check engine light, it is crucial to address the root cause of the problem to prevent further transmission damage and ensure proper vehicle operation.

8. Can a DIY enthusiast fix OBDII code P1D99 at home?

- Depending on the extent of the issue, DIY enthusiasts with the necessary tools and knowledge may be able to address minor causes of P1D99, such as low transmission fluid levels. However, more complex repairs may require professional intervention.

9. How much does it cost to repair OBDII code P1D99?

- The cost of repairing code P1D99 can vary widely depending on the specific cause of the issue, the extent of damage, and labor costs. It is advisable to obtain multiple quotes from reputable mechanics or repair shops.

10. How can I prevent OBDII code P1D99 from recurring in the future?

- Regular maintenance of the transmission system, including timely fluid changes, inspection of clutch components, and addressing any minor issues promptly, can help prevent the recurrence of OBDII code P1D99.