AutoCodes – Cadillac – B370B Cadillac

B370B Cadillac Code - Rear Wiper Function Control Circuit Short to Ground

Quick Answer

The Body Control Module (BCM) controls the rear wiper motor based on an input from the rear wiper switch, which is part of the turn signal/multifunction switch. Common causes include Faulty Rear Window Wiper Motor, Rear Window Wiper Motor harness is open or shorted, Rear Window Wiper Motor 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: B370B Cadillac indicates Rear Wiper Function Control Circuit Short to Ground.
Common causes: Common causes include Faulty Rear Window Wiper Motor, Rear Window Wiper Motor harness is open or shorted, Rear Window Wiper Motor 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 538

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 Mar 13, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B370B Cadillac Description

The Body Control Module (BCM) controls the rear wiper motor based on an input from the rear wiper switch, which is part of the turn signal/multifunction switch. The rear wiper switch uses a resistor ladder to determine low speed, intermittent, and rear washer operation. A constant B+ and ground are supplied to the rear wiper motor. When rear wiper operation is requested, the BCM sends serial data messages. When the rear wiper switch is placed in the low speed, intermittent, or rear washer position, the voltage is pulled down through a different resistor in the resistor ladder, reducing the voltage seen at the BCM. The BCM will respond by commanding the specific rear wiper function.
The BCM monitors the liftgate ajar signal circuit, and the BCM will disable the function of the rear wiper motor if the liftgate of liftglass is ajar or open.
The Diagnostic Trouble Code (DTC) sets when a short to voltage, short to ground or open or high resistance is detected in the rear wiper relay control circuit.

OBDII Code B370B Cadillac - Rear Wiper Function Control Circuit Short to Ground - AutoCodes.com — B370B Cadillac Code - Rear Wiper Function Control Circuit Short to Ground

What does this mean?

What are the Possible Causes of the DTC B370B Cadillac?

Faulty Rear Window Wiper Motor
Rear Window Wiper Motor harness is open or shorted
Rear Window Wiper Motor circuit poor electrical connection
Faulty Body Control Module (BCM)

How to Fix the DTC B370B Cadillac?

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 B370B Cadillac 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 B370B Cadillac Code

1. What does the OBDII code B370B mean on a Cadillac?

The code B370B indicates a problem with the rear wiper function control circuit, specifically a short to ground condition.

2. What are the common symptoms of code B370B on a Cadillac?

Symptoms may include the rear wiper not functioning, operating intermittently, or being stuck in one position.

3. What causes the B370B code to appear on a Cadillac?

The code is typically caused by damaged wiring, a shorted rear wiper motor, a faulty control module, or corrosion in the circuit.

4. How can I diagnose the B370B code on my Cadillac?

Start by inspecting the rear wiper circuit for damaged or frayed wires, check the wiper motor for proper function, and test for continuity in the circuit to locate the short.

5. Can I still drive my Cadillac with code B370B?

Yes, you can still drive the vehicle, but the rear wiper may not function properly, which could reduce visibility in adverse weather conditions.

6. How do I fix the B370B code on a Cadillac?

Repairs may include replacing damaged wiring, repairing corroded connections, or replacing the rear wiper motor or control module.

7. How much does it cost to repair a B370B code on a Cadillac?

Repair costs vary but typically range from $100 to $400, depending on whether wiring repairs or component replacements are needed.

8. Can a blown fuse cause the B370B code on a Cadillac?

A blown fuse is unlikely to directly cause this code but could indicate a related issue with the rear wiper circuit or motor.

9. How do I prevent the B370B code from occurring again?

Regularly inspect and maintain the rear wiper system, ensuring that wiring and connectors are intact and free of corrosion.

10. Do I need a mechanic to fix the B370B code on my Cadillac?

If youâ€™re experienced with electrical diagnostics and repairs, you can attempt to fix the issue yourself; otherwise, itâ€™s best to consult a professional mechanic.