deepa1600

So, i was having this code for couple of days now and everytime i cleared it, it came back with a vengeance. So, I changed 3rd gear switch and before that i followed service manual, step by step, for diagnosis (details on code P0848 diagnosis in auto transmission pdf file @ pages 184-187 and replacement of 2nd, 3rd and 4th switch @ pages 296-299) and car has been fine since i changed it yesterday, I drove about 200 km (125 miles) after changing and no codes so far. I am planning to change 2nd and 4th gear switches as well and will see if can create a DIY since i couldn't find one for our Car. See below for part #'s i found from www.oemacuraparts.com ) and don't forget to change washers as well.
2nd/4th switch (i think they are same): 28600-RAY-013 (old part # is 28600-RAY-003)
3rd switch: 28610-RKE-004 (old part #'s are 28610-RAY-003, 28610-RAY-013)

Walfunk

AFS, Emission and Transmission codes but P1717 is the error...looking forward to the DIY, it says my 4th gear switch is the problem...

rlx015

My car has the same behavior with codes: my wife was driving RL today and car popped "Check emissions system", "D" was blinking, check adaptive front lighting system, check transmission system, and P0848 code showed.

Question: if it's P0848 code there, is it possible all these codes / messages popped up just because of the 3rd switch AT circuit or whatever code matches in the stickie on this forum?
I plan to take it to the dealer possibly tomorrow to have it checked out. From what I see part is around $50-60, wondering if the labor is intensive, and what dealer will be asking for fixing this...

Thanks!!

deepa1600

Hi, it was the 3rd gear switch in my case and it's highly likely the same in your case. I have attached diagnostic (start from step 7) and replacement pages of the manual. It's fairly easy to replace. Make sure you remove and replace old washer from the switch. It's located behind the front driver wheel behind plastic covers,

rlx015

Thank you!
When your lights came back, did your "check emission system" light remain on dashboard while afs and P0848 codes were only showing on navi screen in messages?
That is my scenario, so I am suspecting emission test started the ordeal but really hoping it is the P0848 switch as it will be lot cheaper to fix vs emission system repair...

deepa1600

After I replaced the switch i cleared codes from ECU and all three lights were gone. But i still get emission light once in a while with code P0420 (i think bad cat or bad O2 sensor) but i haven't bothered with it, i just clear the code and carry on. I have replaced all three switches, the 2nd and 4th i replaced when i did TB and waterpump. So i am guessing you are from US because in Canada all the codes and warning show up in MID not on big center nav display.

rlx015

rlx015

deepa1600

I think maybe wait and watch for couple days if the car acts up again because it could very well have been bad battery. RL is very sensitive to low battery voltage and will cause lot of sensors to go crazy. What is the mileage on it? Because if it's high then you might as well replace the switch as a precaution. And yes you need #12 & #18 (https://www.acuraoemparts.com/auto-parts/2006/acura/rl-sedan/rl-h-hawaii-trim/5-speed-automatic-engine/transmission-automatic-cat/at-sensor-solenoid-scat). One more thing in my car if i had flashing D light due to the switch it never went into 5th gear unless i cleared the codes.

rlx015

Great - thank you. I will pick up a washer from local Honda dealer that has it in stock.
I will be taking car probably later today to get all these installed and will report back on whether lights re-occur after all parts are replaced.

rlx015

@deepa1600 - did you get VSA and triangle exclamation mark after replacing your parts?
This may be relevant to the positive cable terminal replacement I had my mechanic do... now I am checking to see how to reset the VSA /!\ lights (84) as my VSA and TCS are currently not working. Someone mentioned this may have happened due to navi/cd changer being "disconnected" - but in fact they were replacing the positive terminal cables and that is probably the culprit ...

Anyone know how to easily reset VSA /!\ lights and get the car back to its glory of no lights on the control panel?

deepa1600

Hey, i didn't get any Vsa lights. I would recommend checking fuses for the VSA if fuse is good then disconnect negative battery cable and wait for couple minutes and then reconnect and check again.

rlx015

deepa1600

I am glad the issue is resolved.

rlx015

Well, I think I spoke too soon. Next day after all was "well", all the same lights came back... First check emission system and engine light... AFS, and then transmission. Same codes, same all ... Went back to mechanic who did all the work and left car for longer diagnostics they will need to do, as now wiring or shorted wire is suspected and becomes bit of a needle in a haystack search.

Fingers crossed it happens soon..

rlx015

UPDATE: Mechanic found loose connectivity with 3rd switch AT part, as they explained some wiring around it was loosing contact, and they fixed it.
I could not talk to the mechanic directly as he was not there when I picked up my car, but so far all works no issues, no lights or anything.

rlx015

All lights are back again.. so far money spent $600+ ... Will update... May be time to let go of the car...

RL09

I remember having posted in a similar thread to this what I noticed on multiple lights popping up and my feeling is it is low current.

I get the same 3 lights, airbag, acc,cmbs, like once or twice a month.. I particularly notice it when I honk the horn for a few seconds when there's a dumb-ass not looking where he's going. It even sometimes comes instantly together with my slamming the horn, and if i do so for a second only, only one light comes on, then turns off.

i feel its the module that distributes current - if something like that exist - that's faulty. Coz my acc and cmbs sensors work fine, and my battery is a brand new gel battery with double the stock capacity...

rlx015

Gotta hunt electrical gremlins ... In all instances of lights coming up, it starts out of very random in this order:
1. At the same time, "D" starts blinking and first message and light that comes is "Check emissions system"
2. It then follows with "Check AFS" or whatever exact verbiage is...
3. Transmission message comes up and code P0848 shows as well...
4. Within next 10-12hours "Check Emission System" message and engine light goes away on it's own while two messages remain in Navi (which I have cleaned before, but come back).

So far replacement of battery happened after first set of lights...
Battery cables were replaced because my positive terminal was cracked and needed replacing anyway
3rd gear switch AT pressure part was replaced with the washer as well...

I suspect it is nothing faulty, but a short causing this behaviour as the car drives perfectly and as usual.

Will update what dealer says on Tuesday...

RL09

Prepare to be offered to chane a shitload of sensors, and prepare yourself to say no.

Unless they wanna do it, and refund you if lights come back on.

My money is on the dealer not knowing the real cause.

HDNBenjamin

I had a similar occurance while driving my car on the freeway a few years back when I had 90k on the odometer. Went straight to my mechanic and he took off the valve cover, used compressed air to clean the carbon buildup through the EGR port, while i revved the engine, I could see plenty of black smoke escaping from the exhaust. We did this a couple of times..no codes ever since. He mentioned that this is a common problem. Give it a try..He charged me $30 to do this..I probably could do this on my own but I do not have an air compressor

rlx015

Update: Dealer was able to install/replace correct sensor/part (3rd gear pressure switch AT) ...Previous mechanic who "fixed" it has not dealt with Acura's, not lately, but ever

Note to all: Dealer mentioned if there is a blinking "D" as part of these flashing lights, lamps, messages, etc. it is definitely pressure switch that is the culprit.

HDNBenjamin

Thanks for the update. I may decide to replace it early as prevemtative maintenance at 150k. I am at 123k right now lol.

rlx015

I also plan to check EGR Valve as well - plus clean throttle body as these two may affect some issues (dependent when was the last time these were cleaned... if ever )

Quick Question: Are these pressure switches AT all the same for different gears or different?

Thanks for all the guidance!

mrm143

I am replying to watch this thread... Been having the same issue since i got the car a few years ago... Replaced battery a few times, always comes back... Same lights, cant shift to 5th gear.. pull over turn off/on car and it goes away... Doesn't happen frequently but aggravating when it does...

Let me know if after replacing that switch if it comes back... Thanks

rlx015

Happy to report that lights have not come back since the dealer fixed it.
Do you get blinking "D" when you experience issues described above? If yes, I'd recommend perhaps changing all of the pressure switches (however many there is lol) - they are about $50-70/each at the dealer, plus labor I am sure is not too much to cover this... however, it may be $500 you spend that does not fix your problem, as you are having issues with trans not going into 5th...

mrm143

Are you still not having any issues? Mine is becoming a multiple times per day thing now and getting EXTREMELY annoying.... I want to make sure it still is ok so i can order a sensor...

mrm143

It only doesn't go into 5th when the D is blinking and all the other lights come on... turn of car and start again, its fine...

PebblesF

My 2010 MDX recently began intermittent starts in second gear. Bad shifting and sudden downshifts when I was slowing down. Paddle shifters did not work nor did the shift display show my gear position in Sport/Manual mode 1,2,3,4,5,6. Very harsh shifts and sudden lurches when tranny would shift with speed. No codes and no dashboard notice of any kind. The problem lasted for 2 days then went away. A week later it began again for a few hours. Checked for codes and found P0848. I will be replacing the third tranny pressure switch in the next few days. Based on the threads I read, it should solve the problem. I will post later to confirm.

PebblesF

Update,

I evaluated all transmission pressure switches to determine which codes they trip when the sensor is shorted (or failed closed). See attached. Based on this I determined that my intermittent bad shifting and starts in second and third gear were related to a bad "Switch B" see image for related codes and switches.

I replaced the switch and no problems since. I hope this is helpful to all with bad shifts or erratic badly timed shifts.

Shyne Nunez

2005 acura rl replaced trans sensor switch twice still getting same code what else could be the problem ?

PebblesF

I would suggest you check that you replaced the correct switch. They are located very close to each other and can be mistaken. Also unplug the switch beside the one you are replacing and verify that you trigger he corresponding code on my attached picture. Also pull back the wiring harness tape on the sensor and make sure the wire is not damaged cut or torn. What is the code you are seeing?

PebblesF

I would suggest you check that you replaced the correct switch. They are located very close to each other and can be mistaken. Also unplug the switch beside the one you are replacing and verify that you trigger he corresponding code on my attached picture. Also pull back the wiring harness tape on the sensor and make sure the wire is not damaged cut or torn. What is the code you are seeing?

Shyne Nunez

po848 and thnx

DocN13a

I know this thread is old, but I just had this code pop up this weekend on my 2006 RL (212k miles and still going!)
P0848 along with Active Head Lights and Power Steering issue.
Took to Stealership (out of convenience) already knowing what the issue might be thanks to this forum. They confirmed it was the 3rd gear sensor and fixed it yesterday. They replaced it and all codes were gone. They also told me positive battery cable was loose (which was mentioned by them a few months ago when my battery was hesitating to start so I replaced the battery, and it has been fine) and needed to be replaced (costing 400$!) along with over 5k of other stuff I dont plan on doing (lower ball joints have had play for over 5 years, oil gasket rear main seal is supposedly leaking, motor mounts). Is the positive battery cable issue common? I figured it was fine as I haven't really had any other issues. The cost for lower control arms and rear main seal were outrageous and more than the car is worth. Are these things even necessary if I am not having any difficulty and might have the car another year or two. Is it ok to use aftermarket parts for these things or OEM? I've owned the car for over 10 years (I'm second owner, bought it with 30k) and luckily only regular maintenance needed (timing belt/water pump, spark plugs, oil changes, tires brakes and rotors) O2 sensor went bad earlier this year. Seems like nothing on the road compares to it to make me want to get rid of it since its paid off.