AutoCodes – GMC – P0815 GMC

P0815 GMC Code - Upshift Switch Circuit

Quick Answer

The Driver Shift Request (DSR) allows the driver to select the desired range of gears for current driving conditions. Common causes include Faulty Transmission Shift Lever, Transmission Shift Lever harness is open or shorted, Transmission Shift Lever 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: P0815 GMC indicates Upshift Switch Circuit.
Common causes: Common causes include Faulty Transmission Shift Lever, Transmission Shift Lever harness is open or shorted, Transmission Shift Lever 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 356

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 Aug 02, 2022

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P0815 GMC Description

The Driver Shift Request (DSR) allows the driver to select the desired range of gears for current driving conditions. The DSR shift system is activated when the gear selector is in the manual position. The DSR system is deactivated in all other range positions. Pressing the plus (+) switch once will command the Body Control Module (BCM) to signal the Transmission Control Module (TCM) to upshift to the next high gear. Pressing the minus (−) switch once will command the BCM to signal the TCM to downshift to the next lowest or previous gear. The TCM will not allow a downshift if the transmission is compromised by over-speeding. The automatic transmission manual shift switch is comprised of three different resistor values in series and two switches. The BCM supplies a 12-volt circuit to the automatic transmission manual shift switch. The signal circuit varies the voltage back to the body control module depending on which switch is depressed. The Diagnostic Trouble Code (DTC) will be set when the BCM detects a stuck On Tap Up switch for 1 second in Park or Neutral or the BCM detects a stuck On Tap Up switch for 10 minutes in any forward gear.

OBDII Code P0815 GMC - Upshift Switch Circuit - AutoCodes.com — P0815 GMC Code - Upshift Switch Circuit

What does this mean?

What are the Possible Causes of the DTC P0815 GMC?

Faulty Transmission Shift Lever
Transmission Shift Lever harness is open or shorted
Transmission Shift Lever circuit poor electrical connection
Faulty Body Control Module (BCM)

How to Fix the DTC P0815 GMC?

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 P0815 GMC 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 P0815 GMC code?

Need more information on how to fix the P0815 GMC code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0815 GMC code diagnosed by a professional: Find a repair shop in your area

Information for Specific GMC Models

P0815 2014 GMC Sierra — Upshift Switch Circuit
P0815 2015 GMC Sierra — Upshift Switch Circuit
P0815 2016 GMC Sierra — Upshift Switch Circuit
P0815 2017 GMC Sierra — Upshift Switch Circuit
P0815 2018 GMC Sierra — Upshift Switch Circuit

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 P0815 GMC Code

1. What does the OBDII code P0815 mean on a GMC?

Code P0815 on a GMC indicates a problem with the upshift switch circuit, which is responsible for detecting and processing gear shift signals.

2. What are the common symptoms of the P0815 code in a GMC?

Symptoms may include difficulty shifting gears, the transmission staying in one gear, illuminated check engine light, or reduced vehicle performance.

3. What causes the P0815 code to appear in a GMC vehicle?

Common causes include a faulty upshift switch, damaged wiring or connectors in the upshift circuit, or a malfunctioning transmission control module (TCM).

4. How can I diagnose the P0815 code on a GMC?

Use an OBDII scanner to confirm the code, then inspect the upshift switch, wiring, and connectors for damage or loose connections. Test the switch and circuit continuity if no visible issues are found.

5. Can I drive my GMC with the P0815 code?

Driving with the P0815 code is not recommended, as it can lead to unpredictable shifting behavior and potential transmission damage.

6. How do I fix the P0815 code on a GMC?

Repairs may include replacing a faulty upshift switch, repairing or replacing damaged wiring or connectors, or reprogramming or replacing the TCM if necessary.

7. How much does it cost to repair the P0815 code in a GMC?

Repair costs vary depending on the issue, but replacing an upshift switch typically costs $100â€“$300, while TCM repairs may range from $500â€“$1,000.

8. Can a software update clear the P0815 code in a GMC?

In some cases, a software update for the TCM may resolve the issue, especially if itâ€™s caused by a programming error.

9. What tools are needed to troubleshoot the P0815 code in a GMC?

Tools include an OBDII scanner, a multimeter for testing electrical circuits, and possibly a repair manual for your specific GMC model.

10. Is the P0815 code specific to GMC vehicles?

No, the P0815 code is a generic OBDII code that can appear in other vehicles as well, but its diagnosis and repair may vary depending on the make and model.