P1126 Nissan Code - Thermostat Function
Quick Answer
Engine coolant temperature has not risen enough to open the thermostat even though the engine has run long enough. Common causes include Low engine coolant level, Faulty Thermostat, Leakage from sealing portion of thermostat. 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
- P1126 Nissan indicates Thermostat Function.
- Common causes
- Common causes include Low engine coolant level, Faulty Thermostat, Leakage from sealing portion of thermostat.
- 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 P1126 Nissan Description
Thermostat Function is for 2000-2001 Nissan models.
What are the Possible Causes of the DTC P1126 Nissan?
- Low engine coolant level
- Faulty Thermostat
- Leakage from sealing portion of thermostat
- Engine coolant temperature sensor
How to Fix the DTC P1126 Nissan?
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
For Nissan vehicles other than the 2000-2001 models see: P1126 Nissan
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P1126 Nissan 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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Information for Specific Nissan Models
- P1126 2000 Nissan Altima Sedan — Thermostat Function
- P1126 2001 Nissan Altima Sedan — Thermostat Function
- P1126 2002 Nissan Altima Sedan — Throttle Control Motor Relay Circuit Open
- P1126 2003 Nissan Altima Sedan — Throttle Control Motor Relay Circuit Open
- P1126 2004 Nissan Altima Sedan — Throttle Control Motor Relay Circuit Open
- P1126 2005 Nissan Altima Sedan — Throttle Control Motor Relay Circuit Open
- P1126 2000 Nissan Maxima — Thermostat Function
- P1126 2001 Nissan Maxima — Thermostat Function
Frequently Asked Questions about P1126 Nissan Code
1. What does the OBDII code P1126 mean on a Nissan?
P1126 on a Nissan indicates a "Thermostat Function" issue, meaning the ECU detects that the thermostat is not operating properly.
2. What are the common symptoms of a P1126 code?
Symptoms may include the engine taking too long to warm up, poor fuel efficiency, engine overheating, or the Check Engine Light turning on.
3. What causes the P1126 code on a Nissan?
Common causes include a stuck open or closed thermostat, low coolant levels, a malfunctioning coolant temperature sensor, or wiring/connection issues.
4. Can I drive my Nissan with a P1126 code?
Driving with a P1126 code is not recommended, as it can lead to engine overheating or poor fuel efficiency, potentially causing long-term engine damage.
5. How is the P1126 code diagnosed?
A mechanic will use an OBDII scanner to confirm the code, inspect the thermostat, check coolant levels, and test the coolant temperature sensor and related wiring.
6. How do I fix the P1126 code on my Nissan?
Fixes may include replacing the thermostat, refilling or flushing the coolant, repairing wiring, or replacing a faulty coolant temperature sensor.
7. How much does it cost to repair a P1126 code on a Nissan?
The cost to repair a P1126 code typically ranges between $150 and $300, depending on whether the thermostat or other components need replacement.
8. Can a dirty coolant system cause a P1126 code?
Yes, a dirty or clogged coolant system can restrict proper coolant flow, potentially causing the thermostat to malfunction and trigger the P1126 code.
9. What happens if I ignore a P1126 code?
Ignoring a P1126 code could lead to engine overheating, reduced performance, and possible long-term engine damage due to improper temperature regulation.
10. Does a P1126 code always mean the thermostat is bad?
Not necessarily. While the thermostat is the most common culprit, issues with coolant levels, wiring, or the coolant temperature sensor can also trigger the code.
Discuss the causes and fixes for P1126 Nissan OBDII Code
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I have a 2001 nissan frontier 4cyl truck i have replaced the thermostat and the sensor and still get the error any ideas
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The P1126 means that the coolant temperature sensor reading it out of factory specifications. For example, after 5 min of driving, the temperature should read around 100F (Temperature and driving condition may vary). If is not at that temperature, then the ECM calculates that the thermostat is not opening and set the thermostat function test.
If you already replaced the thermostat and sensor, then the next thing is to check for clogged radiator or coolant system. Clogged system will cause a no engine coolant flow, so the thermostat will never open or may stay open all the time.
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03 maxima pulled code p1126, also have been getting really bad fuel economy last little while. Pulled the thermostat out and seems to pass the boiling water test (I think), anything else to look for? Should I replace or leave original in?
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The P1126 code is for the thermostat on Nissan models 2000-2001 only (See "Tech Notes" above)
For your 2003 Nissan Maxima the P1126 code is for the: Throttle Control Motor Relay
P1126 NISSAN - Throttle Control Motor Relay Circuit Open
Read more: https://www.autocodes.com/p... -
Got a 2001 Sentra and its throwing a p1126 code? Check engine light came on last Thursday, & the next night car almost died on the interstate when stuck in stand still tracffic.
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Did the engine overheated?
For the P1126 on the 2001 Nissan Sentra the most likely cause of the problem is the thermostat.
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