Code P0841, where is the transmission fluid pressure sensor/ switch “a” circuit range/performance?

CRIS9542

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2016 NISSAN ALTIMA
2.5L
4 CYL
2WD
AUTOMATIC
55,000 MILES

Check engine light gave the code P0841.

Thursday, June 19th, 2025 AT 9:50 PM

5 Replies

KEN L

MASTER CERTIFIED MECHANIC
53,862 POSTS

This can be the transmission is low on fluid, or the pressure pump has gone out FYI. We can try the sensor first. This is a CVT unit which is known to go out.

Transmission Fluid Pressure Sensor-Switch “A” - Circuit Range/Performance trouble code.

The sensor is inside the control valve. If the fluid is burnt, then the transmission will need a rebuild which is common for these. Check out the images (below). Let us know how it goes.

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Friday, June 20th, 2025 AT 1:31 PM

CRIS9542

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Can the sensor be replaced or does the control valve need to be replaced?

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Friday, June 20th, 2025 AT 1:58 PM

CRIS9542

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I also found a small leak on one of the side of the oil pan. The transmission fluid was also recently changed like 3 months ago. Would it be possible its throwing a code because it’s low on transmission oil?

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Friday, June 20th, 2025 AT 2:02 PM

CRIS9542

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Also do you have a photo of the sensor or know where they sell the Sensor?

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Friday, June 20th, 2025 AT 3:05 PM

KEN L

MASTER CERTIFIED MECHANIC
53,862 POSTS

Yes, it can be low fluid causing the code. I would make sure the unit is full and then clear the codes. Yes the control valve will nee to be replaced because the sensor is inside of it. You will need to pump fluid into the overflow plug and allow it to run our with the engine running. Here is a guide to help and images below to help you.

Type .................... Genuine NISSAN CVT Fluid NS-3

https://www.2carpros.com/articles/how-to-check-and-add-transmission-fluid

Check out the images (below). Let us know how it goes

Images (Click to make bigger)