P0708 2016 GMC Sierra Code - Transmission Range Switch Circuit High Voltage
Quick Answer
The Transmission Internal Mode Switch (IMS) consists of 5 internal switches, A, B, C, P, and Neutral Start. Common causes include Faulty Transmission Internal Mode Switch (IMS), Transmission Internal Mode Switch harness is open or shorted, Transmission Internal Mode 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
- P0708 2016 GMC Sierra indicates Transmission Range Switch Circuit High Voltage.
- Common causes
- Common causes include Faulty Transmission Internal Mode Switch (IMS), Transmission Internal Mode Switch harness is open or shorted, Transmission Internal Mode 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.
Code P0708 2016 GMC Sierra Description
The Engine Control Module (ECM) supplies a signal circuit to the neutral start switch. The ECM uses the state of the neutral start switch state as confirmation that the transmission is in neutral or park before the engine starter is engaged.
The Diagnostic Trouble Code (DTC) will be set when the TCM detects the internal mode switch is reporting an illegal range for greater than 1 s.
What are the Possible Causes of the DTC P0708 2016 GMC Sierra?
- Faulty Transmission Internal Mode Switch (IMS)
- Transmission Internal Mode Switch harness is open or shorted
- Transmission Internal Mode Switch circuit poor electrical connection
- Faulty Transmission Control Module (TCM)
How to Fix the DTC P0708 2016 GMC Sierra?
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.
Code Tech Notes
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P0708 2016 GMC Sierra 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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Frequently Asked Questions about P0708 2016 GMC Sierra Code
1. What does the P0708 code mean on a 2016 GMC Sierra?
The P0708 code indicates a high voltage signal in the transmission range switch circuit, which monitors gear selection.
2. What are the symptoms of a P0708 code in a 2016 GMC Sierra?
Common symptoms include difficulty shifting gears, the transmission stuck in one gear, the check engine light illuminated, or the vehicle entering limp mode.
3. What causes the P0708 code on a 2016 GMC Sierra?
Potential causes include a faulty transmission range sensor, damaged wiring or connectors in the circuit, or issues with the vehicle's powertrain control module (PCM).
4. Can I drive my 2016 GMC Sierra with a P0708 code?
It’s not recommended to drive for long distances as the transmission may not shift properly, which can lead to further damage or unsafe driving conditions.
5. How do I diagnose a P0708 code on a GMC Sierra?
Start by inspecting the wiring and connectors for damage or corrosion, check the transmission range sensor for proper operation, and verify voltage and signal readings using a multimeter.
6. How much does it cost to fix a P0708 code on a 2016 GMC Sierra?
The repair cost depends on the issue, ranging from $150–$400 for sensor replacement, while wiring repairs can vary based on complexity.
7. Will clearing the P0708 code fix the problem?
Clearing the code may turn off the check engine light temporarily, but it will return if the underlying issue isn’t resolved.
8. What tools are needed to fix the P0708 code on a 2016 GMC Sierra?
Basic tools include a multimeter, OBDII scanner, and possibly a replacement transmission range sensor if it’s defective.
9. Does the P0708 code always mean the transmission range sensor is faulty?
No, it can also be caused by wiring issues, connector damage, or problems with the PCM.
10. Can a bad battery cause a P0708 code in a 2016 GMC Sierra?
While uncommon, low or unstable battery voltage can sometimes interfere with sensor signals and trigger the code.
Discuss the causes and fixes for P0708 2016 GMC Sierra OBDII Code
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