QX80 Showing P1815 Manual Mode Switch Code

[errece]

Hello everyone,

My 2015 QX80 just recently showed a P1815 - Transmission Code - Manual Mode Switch. Does anyone know what this means?, what to look for?, is there a fix? It has 197k (Kilometers not miles) on the odometer

I've maybe engaged the manual mode 3 or 4 times in its lifetime, it just goes on P, R, N or D, that's it. So not sure where this code be coming from. I cleared the light once, it came back on about 300 km later, and cleared it again, but of course I want to know what I might be facing with that code.

This SUV has a P0420 code that's been there for the longest time, I replaced the upstream sensor, cleaned injectors, replaced spark plugs and keeps coming back, that one I just clear it every so often and not concerned about that one, but the P1815 is a new occurence and I noticed it trying to clear what I thought was the usual P0420.

Appreciate any help.
Thank you

[VStar650CL]

P1815 is usually a sticky or bad microswitch in the shifter assembly. Did you spill anything down there? The up/down switches are in series with the "manual" throw on the Manual Mode switch, and the code generally means one of those switches is showing active even though the "auto" throw on the MM switch also shows active. That condition is impossible when the switches are working right, so it causes a code.

[errece]

P1815 is usually a sticky or bad microswitch in the shifter assembly. Did you spill anything down there? The up/down switches are in series with the "manual" throw on the Manual Mode switch, and the code generally means one of those switches is showing active even though the "auto" throw on the MM switch also shows active. That condition is impossible when the switches are working right, so it causes a code.

Thank you VStar650CL,

Nothing spilled on my watch, but now I'll interrogate my wife and kids in case someone's hiding something. Is it a reasonably easy fix or is it a $1,500 at the dealership kind of problem?

[VStar650CL]

From what I see online it looks similar (maybe identical) to the gen2 Armadas. They definitely use the same shifter, but the console details may differ slightly. The Armada units aren't difficult to remove and clean if the problem is spilled soda pop. Here's a vid of how to remove the shift knob...
https://www.youtube.com/watch?v=jFg3HspS7wM
...then the top of the console just pops loose with a plastic prybar. Disconnect the electricals, then there are 10mm screws at each corner of the shifter which you reach with a socket, a long extension, and maybe a swivel. Have a magnet on hand for retrieving and replacing the lefthand screws. Then pry the shift cable horseshoe clip loose from the foot of the shifter with a canted prybar, then pry the end of the cable loose from the pivot pin. Pop the electrical connector and out it comes. Here are the relevant FSM sections, but the console shouldn't need to come out as the FSM instructs. See TM-184 and IP-23:
https://www.nicoclub.com/service-manual ... 5%2Ftm.pdf
https://www.nicoclub.com/service-manual ... 5%2Fip.pdf
This parts drawing should also help you out:
https://www.infinitipartsdeal.com/parts ... evice.html?

If you find gunk in there, clean it with water first and then Drygas in a spray bottle (alcohol and other solvents generally won't touch dried Pepsi or Dunkin). Try to avoid getting water on the shift lock solenoid, and afterward either sun-dry the assembly or use compressed air if you have it.

If you don't find any gunk in there it becomes more complicated, but we'll discuss that bridge if you come to it.

[errece]

From what I see online it looks similar (maybe identical) to the gen2 Armadas. They definitely use the same shifter, but the console details may differ slightly. The Armada units aren't difficult to remove and clean if the problem is spilled soda pop. Here's a vid of how to remove the shift knob...
https://www.youtube.com/watch?v=jFg3HspS7wM
...then the top of the console just pops loose with a plastic prybar. Disconnect the electricals, then there are 10mm screws at each corner of the shifter which you reach with a socket, a long extension, and maybe a swivel. Have a magnet on hand for retrieving and replacing the lefthand screws. Then pry the shift cable horseshoe clip loose from the foot of the shifter with a canted prybar, then pry the end of the cable loose from the pivot pin. Pop the electrical connector and out it comes. Here are the relevant FSM sections, but the console shouldn't need to come out as the FSM instructs. See TM-184 and IP-23:
https://www.nicoclub.com/service-manual ... 5%2Ftm.pdf
https://www.nicoclub.com/service-manual ... 5%2Fip.pdf
This parts drawing should also help you out:
https://www.infinitipartsdeal.com/parts ... evice.html?

If you find gunk in there, clean it with water first and then Drygas in a spray bottle (alcohol and other solvents generally won't touch dried Pepsi or Dunkin). Try to avoid getting water on the shift lock solenoid, and afterward either sun-dry the assembly or use compressed air if you have it.

If you don't find any gunk in there it becomes more complicated, but we'll discuss that bridge if you come to it.

Excellent, thank you so much for the explanation and links, I've saved everything and now I just need to plan the few hours on a weekend to get it done.

[VStar650CL]

[08FrontierFixer]

If replacing the sensors/solenoids does not work, another cause can be a worn grommet where the shifter connects to the cable. The extra play sends conflicting signals to the ECU (e.g. one sensor says it's in N while the other says it's in D). Eventually the cable will fall off, if this is the issue, so keep it in mind as you search for the solution. It is a much more common occurrence than the answers on these posts might suggest, and a <$10 grommet is better than throwing the parts book at the vehicle. Best of luck!

[VStar650CL]

If replacing the sensors/solenoids does not work, another cause can be a worn grommet where the shifter connects to the cable. The extra play sends conflicting signals to the ECU (e.g. one sensor says it's in N while the other says it's in D). Eventually the cable will fall off, if this is the issue, so keep it in mind as you search for the solution. It is a much more common occurrence than the answers on these posts might suggest, and a <$10 grommet is better than throwing the parts book at the vehicle. Best of luck!

If the problem was in the PRNDL indications the transmission would be throwing a P0705 and/or a C1A24 for the Range Switch. P1815 is for the Manual Mode switch (which your Frontier doesn't have), which is inside the shifter assembly and not the transmission. It has nothing at all to do with the cable.