P1686 Buick Code - Transmission Control Module Power Up Temperature Sensor Circuit High Voltage
Quick Answer
The Transmission Control Module (TCM) power up the temperature sensor is located inside of the control solenoid (w/body and TCM) valve assembly and has no serviceable parts. Common causes include Reprogram TCM and recheck code, Replace Transmission Control Module (TCM) Sensor/body assembly one piece. 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
- P1686 Buick indicates Transmission Control Module Power Up Temperature Sensor Circuit High Voltage.
- Common causes
- Common causes include Reprogram TCM and recheck code, Replace Transmission Control Module (TCM) Sensor/body assembly one piece.
- 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 P1686 Buick Description
What are the Possible Causes of the DTC P1686 Buick?
- Reprogram TCM and recheck code
- Replace Transmission Control Module (TCM) Sensor/body assembly one piece
How to Fix the DTC P1686 Buick?
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 P1686 Buick 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 P1686 Buick Code
1. What does the OBDII code P1686 mean on a Buick?
The P1686 code indicates that the Transmission Control Module (TCM) has detected a high voltage issue in the power-up temperature sensor circuit.
2. What are the common symptoms of code P1686 on a Buick?
Symptoms may include erratic shifting, the transmission entering limp mode, an illuminated check engine light, and reduced overall vehicle performance.
3. What causes the P1686 code to appear on a Buick?
Common causes include damaged or corroded wiring, a faulty TCM, a defective temperature sensor, or issues with the vehicle’s power supply to the TCM.
4. How can I diagnose the P1686 code on my Buick?
Start by inspecting the wiring and connectors for damage or corrosion, check the voltage at the TCM, and test the transmission temperature sensor for proper operation.
5. Can I drive my Buick with the P1686 code active?
It is not recommended, as the transmission may not function properly, potentially leading to further damage or unsafe driving conditions.
6. How is the P1686 code fixed on a Buick?
Repairs may involve replacing damaged wiring, cleaning corroded connectors, replacing the transmission temperature sensor, or, in some cases, replacing or reprogramming the TCM.
7. How much does it cost to repair a P1686 code on a Buick?
Repair costs vary depending on the issue, but replacing a temperature sensor can cost around $100-$300, while TCM replacement or reprogramming may cost $500-$1,500.
8. Can a weak battery cause the P1686 code on a Buick?
Yes, a weak or failing battery can cause power supply issues to the TCM, potentially triggering the P1686 code.
9. Does the P1686 code require a TCM replacement?
Not always. The issue may be resolved by repairing wiring or replacing the temperature sensor. The TCM should be replaced only if testing confirms it is faulty.
10. Will clearing the P1686 code solve the problem on my Buick?
Clearing the code may temporarily turn off the check engine light, but the underlying issue must be addressed to prevent the code from returning.
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