AutoCodes – Generic – B12AB

B12AB Code - Drivers Heated Seat Relay Drive Circuit Shorted To Battery Voltage

Quick Answer

The Heating, Ventilation, and Air-Conditioning (HVAC) Module contains the driver heated seat control button and indicator. Common causes include Faulty Heater Seat Relay, Faulty Heater Mat, Heater Mat harness is open or shorted. Severity is Low - monitor the vehicle and repair when practical. The vehicle can usually be driven if no severe symptoms are present, but symptoms should be checked before extended driving.

What it means: B12AB indicates Drivers Heated Seat Relay Drive Circuit Shorted To Battery Voltage.
Common causes: Common causes include Faulty Heater Seat Relay, Faulty Heater Mat, Heater Mat harness is open or shorted.
Severity: Low - monitor the vehicle and repair when practical.
Can I drive?: The vehicle can usually be driven if no severe symptoms are present, but symptoms should be checked before extended driving.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 932

How popular is this code, among other codes? Low

Repair Importance Level

Low (Monitor) (1 / 3)

Repair Difficulty Level

Intermediate (2 / 3)

What is this?

Table of contents Created and updated by William Orellana on Nov 29, 2024

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code B12AB Description

The Heating, Ventilation, and Air-Conditioning (HVAC) Module contains the driver heated seat control button and indicator. The heated seat system functions independently from the climate control system. A heated seat relay is located underneath the driver seat cushion frame. There are 2 voltage supplies to the heated seat relay. Voltage is supplied from the Smart Junction Box (SJB) heated seat relay enable circuit to the driver heated seat relay coil when the engine is running. Ground is supplied to the opposite side of the driver relay coil by the HVAC module driver heated seat relay drive circuit when the driver heated seat switch button is pressed to energize the relay. This closes the relay contacts to supply battery voltage from the SJB circuit to the driver heater mat circuit. The driver heater mats are directly connected to ground circuit completing the electrical circuit to heat the seat.

OBDII Code B12AB - Drivers Heated Seat Relay Drive Circuit Shorted To Battery Voltage - AutoCodes.com — B12AB Code - Drivers Heated Seat Relay Drive Circuit Shorted To Battery Voltage

What does this mean?

What are the Possible Causes of the DTC B12AB?

Faulty Heater Seat Relay
Faulty Heater Mat
Heater Mat harness is open or shorted
Heater Mat circuit poor electrical connection
Faulty Heating, Ventilation, and Air-Conditioning (HVAC) Module

How to Fix the DTC B12AB?

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 B12AB 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 B12AB code?

Need more information on how to fix the B12AB code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B12AB code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

B12AB Ford — Drivers Heated Seat Relay Drive Circuit Shorted To Battery Voltage
B12AB Lincoln — Drivers Heated Seat Relay Drive Circuit Shorted To Battery Voltage
B12AB Mercury — Drivers Heated Seat Relay Drive Circuit Shorted To Battery Voltage

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 B12AB Code

1. What are the common symptoms of OBDII code B12AB (Drivers Heated Seat Relay Drive Circuit Shorted To Battery Voltage)?

- Common symptoms include a non-functioning or malfunctioning heated seat, a blown fuse related to the heated seat circuit, and potentially a burning smell.

2. What are the possible causes of OBDII code B12AB?

- The code B12AB can be caused by a short circuit in the drivers heated seat relay drive circuit, a faulty seat heater relay, damaged wiring in the circuit, or a malfunctioning control module.

3. How can I diagnose the issue related to code B12AB?

- To diagnose the issue, you can start by checking the fuse related to the heated seat circuit, visually inspecting the wiring for any damage, and using a multimeter to test the relay and circuit components for continuity.

4. Can I continue to drive my vehicle with OBDII code B12AB present?

- It is not recommended to drive with the code B12AB present, as it indicates a fault in the heated seat circuit which could potentially lead to further electrical issues or safety concerns.

5. How can I repair OBDII code B12AB (Drivers Heated Seat Relay Drive Circuit Shorted To Battery Voltage)?

- The repair process for code B12AB involves locating and repairing the short circuit in the drivers heated seat relay drive circuit, replacing any damaged wiring or components, and resetting the fault code using an OBDII scanner.

6. Is it possible to fix OBDII code B12AB myself, or should I seek professional help?

- Depending on your experience and comfort level with automotive electrical systems, you may be able to repair code B12AB yourself by following diagnostic procedures and using the appropriate tools. However, if you are unsure or uncomfortable with the repair process, it is recommended to seek professional help.

7. Are there any preventive measures I can take to avoid OBDII code B12AB in the future?

- To prevent OBDII code B12AB from occurring in the future, you can periodically inspect the heated seat circuit for any signs of wear or damage, avoid overloading the circuit, and ensure proper installation of any aftermarket seat heating components.

8. How long does it typically take to repair OBDII code B12AB?

- The repair time for code B12AB can vary depending on the extent of the issue and your level of experience. In general, diagnosing and repairing a short circuit in the heated seat relay drive circuit can take a few hours to complete.

9. Can OBDII code B12AB affect other electrical systems in my vehicle?

- While code B12AB specifically relates to the drivers heated seat circuit, a short circuit or electrical issue in this area could potentially impact other nearby electrical systems. It's important to address the issue promptly to prevent further complications.

10. Will resetting the OBDII code B12AB make the issue go away permanently?

- Resetting the OBDII code B12AB may temporarily clear the fault code from the system, but if the underlying issue causing the code is not repaired, it is likely to reoccur. It is important to diagnose and fix the root cause of the problem for a permanent solution.