AutoCodes – Ford – P0812 1998 Ford F150

P0812 1998 Ford F150 Code - Reverse Switch Input Circuit Malfunction

Quick Answer

The Transmission Control Module (TCM) monitors the Reverse Switch Input signal. Common causes include Faulty Reverse Input Switch, Reverse Input Switch harness is open or shorted, Reverse Input Switch 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: P0812 1998 Ford F150 indicates Reverse Switch Input Circuit Malfunction .
Common causes: Common causes include Faulty Reverse Input Switch, Reverse Input Switch harness is open or shorted, Reverse Input Switch 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 1,798

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 May 09, 2019

Description
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code P0812 1998 Ford F150 Description

The Transmission Control Module (TCM) monitors the Reverse Switch Input signal. The TCM sets the OBDII code when the Reverse Switch Input is not to factory specifications.

OBDII Code P0812 1998 Ford F150 - Reverse Switch Input Circuit Malfunction - AutoCodes.com — P0812 1998 Ford F150 Code - Reverse Switch Input Circuit Malfunction

What does this mean?

What are the Possible Causes of the DTC P0812 1998 Ford F150?

Faulty Reverse Input Switch
Reverse Input Switch harness is open or shorted
Reverse Input Switch circuit poor electrical connection
Damaged PCM

How to Fix the DTC P0812 1998 Ford F150?

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 does this mean?

Code Tech Notes

The DTC indicates that the voltage is high when it should be low.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0812 1998 Ford F150 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 P0812 1998 Ford F150 code?

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Need Help with the Code?

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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 P0812 1998 Ford F150 Code

1. What does the OBDII code P0812 for a 1998 Ford F150 indicate?

- The code P0812 signifies a Reverse Switch Input Circuit Malfunction in the vehicle.

2. What are the common symptoms of a P0812 code in a 1998 Ford F150?

- Common symptoms include issues with the reverse lights not working properly or the vehicle not starting in reverse gear.

3. What can cause the P0812 code to appear in a 1998 Ford F150?

- The code can be triggered by a faulty reverse switch, damaged wiring or connectors in the circuit, or a problem with the transmission range sensor.

4. How can I diagnose the cause of a P0812 code in my 1998 Ford F150?

- To diagnose the issue, you can visually inspect the reverse switch and its wiring, check the transmission range sensor, and use an OBDII scanner to gather more data about the malfunction.

5. Is it safe to drive my 1998 Ford F150 with a P0812 code?

- It is not recommended to drive the vehicle with a P0812 code as it may lead to safety hazards due to malfunctioning reverse lights or gear engagement issues.

6. How can I repair a P0812 code in my 1998 Ford F150?

- Repairing a P0812 code may involve replacing the faulty reverse switch, repairing damaged wiring or connectors, or adjusting the transmission range sensor as necessary.

7. Can a DIY enthusiast fix a P0812 code in a 1998 Ford F150?

- Depending on your skill level and access to tools, a DIY enthusiast may be able to address the issue by following repair guides or seeking assistance from automotive forums.

8. Will resetting the OBDII system clear a P0812 code in a 1998 Ford F150?

- Resetting the OBDII system may temporarily clear the code, but if the underlying issue is not addressed, the code is likely to reappear upon driving the vehicle.

9. How much does it cost to repair a P0812 code in a 1998 Ford F150?

- The cost of repairing a P0812 code can vary depending on the specific cause of the malfunction, the parts needed for replacement, and whether you choose to perform the repairs yourself or seek professional help.

10. Can a P0812 code in a 1998 Ford F150 affect the overall performance of the vehicle?

- While the P0812 code itself may not directly impact the performance of the vehicle, it is crucial to address the underlying issue promptly to ensure the safe operation of the vehicle.