P1126 & P1126 pending 2001 Nissan Altima -

Question

My service engines came on a few months back. The code was P1126. The day before I unplugged my battery for testing. So I figured it was just the computer resetting. The temperature gauge was working and there was coolant in the container. I erased the code and waited to see if the engine light would come on. Now, months later, it did. Only this time it said P1126 and P1126 pending. Again, there's coolant still in there and the temperature gauge is still working. I had to replace the battery a couple of weeks to a month prior to it turning back on. What could be the problem? Why did it give the code and also say the same code was pending?

Answer 1

Most likely the thermostat needs to be replaced.

P1126 2001 NISSAN ALTIMA - Thermostat Function

Possible causes:
- Low engine coolant level
- Faulty Thermostat
- Leakage from the sealing portion of the thermostat
- Engine coolant temperature sensor