Sparky16

2006 TL - AT, just turned to 70k miles, original owner

All of these happened when I was driving 100+ miles into freeway. I was cruising @73mph with cruise control. I clicked twice on "cruise+" button to go to 75mph - VSA CEL then yellow triangle warning light with flashing D light were lit up at once.

Pulled to the next exit, checked ATF level - ATF level was a bit high but not too high. Restarted went on my way, only CEL stayed on for the next 2 days but nothing unusual noticed.

On the way back home 2 days later, CEL gone, all clear. But all these lit back up at around 100 miles after driving. Driving home(350 mi) via freeway, stopped twice for restroom with these lights on wasn't a problem, not limp home mode.

At home, pulled P0977 code with handheld OBD-II code reader. Malfunction - solenoid B control circuit. Can anyone help to locate where this solenoid B is, and if DIY is doable? Link to DIY w/pictures will be greatly appreciated.

Below are the list of works I performed myself during last 2 months, 500 miles prior to this trip, in chronological order.

*oil w/filter replaced 1,000 miles prior with OEM filter and Mobile 5W-20, at correct level
*3x3 ATF replacement done 6 weeks ago with Redline D4
*ATF filter replaced
*3rd & 4th switches replaced a week later
*brake fluid bled, filled with Dot 4 OEM MB fluid(because I just bought 2 litres to do both ML320 & TL)
*brake pads replaced with OEM pads - 2 weeks, 300miles ago
*no leak on garage floor, ATF or oil

*noticed the gas mileage dropped from 29mpg to about 25mpg and drive wasn't as smooth as it had been, but could been in my mind.

Thanks for your input and help.

vietxquangstah

iTrader: (7)

that code is for transmission pressure switches

check your pressure switches. disconnect and reconnect them

Sparky16

Are you referring 3rd & 4th switches? I know where those two switches are, but don't know others.

Isn't P1740 for TRANNY PRESSURE SWITCHES?

Sparky16

P0977 is NOT for pressure switch. It is for AT shift solenoid B assmembly, #11 shown in red in the illustration below;

I need help how to replace this solenoid B, if DIY is possible. Thanks!

vietxquangstah

iTrader: (7)

Sorry I was wrong. I had a P0843 in the past and didn't remember the exact number but also had a flashing "D" light and assumed it was the same code you got.

P0843 had to do with my transmission fluid pressure sensor.

Sparky16

Understood. AFAIK, there are many reasons for flashing D indicator light. Someone please chime in for P0977 - SHIFT SOLENOID B CONTROL CIRCUIT. Thanks.

mreducated100

I want to say solenoid "B" is connected to the dual linear solenoid A & B which would be #6 in the diagram. It is under the air intake tube and it has a red connector and a black connector connected to it. The B solenoid is the one with the black connector. However, it is one unit unfortunately so it may cost a little bit. It is super easy to change. It takes 10 mm and has 6 screws. I would buy the gasket too. The gasket breaks and gets old. Also, there are 3 small cylinder tubes you will see once you lift the solenoid up. Check those and clear the screens inside of there if there is clutch material built up. There may not be clutch material but just check anyway. Super easy.

Sparky16

Thanks for posting, appreciated.
But I can't understand how the solenoids A & B are connected as ONE unit. Would you be able to show some pics or schematic so I can see it easily? I see parts stores, online or off-line, are selling solenoids A & B separately as separate unit.

Majofo

Could be several issues. First thing is verify you have the up-to-date pcm version. There are some related pcm updates.. and since you threw the code on cruise, the cruise logic interfaces the shift logic so there's some correlation. The root cause seems related to the long cruises you're taking, but it seems like you're in 5th the whole way.. not a lof of shifting going on, so the only thing that jumps at me is moisture, heat and failure. I would definitely ensure no moisture is dripping down on the pcm (probably not, but worth a check - passenger inside foot well). I'd check connections at both ends as well (make sure connections are tight and secure). After that I'd clear the code and cross your fingers that it doesn't come back.

Regarding D4, it's good fluid, I don't suspect it had anything to do with the code. It being a little overfilled is fine as well. There's a overfill valve. Don't need to worry about accelerating the fluid life or causing harm by overfilling. It's also common to see it higher than it actually is for a number of reasons.

Regarding SSB, it stays on (open) from 1st to 3rd. A signal triggering it to go on in cruise can be cruise logic telling system to drop down to 3rd, but I doubt it would be programmed that aggressive. More than likely it's just programmed to increase throttle for such an incremental change. If it has truly failed, not pcm / cruise / shift logic related, just replace it and be done with it. There's a series of checks through HDS that requires the updated pcm that the dealership can do. Might as well have them do the update and the diagnostic. Depending on the price, have them replace it if reasonable, otherwise tell them to get bent, buy the part and do it yourself.

Keep us updated.

Majofo

If you do replace it, replace all the o-rings and gasket as well.

Sparky16

Thanks for your reply and time for lengthy reasoning.
I was on I-5 cruising @75mph, driving on warm desert, but not hot early morning 8:30. A/C was on, but no dripping water inside.

Come to think of it, RPM was just below @3000 @75mph, pretty high for cruising flat area or very slow hill at 5th gear. That makes me to think I was at 4th gear the whole time instead of 5th, thus the lower gas mileage.

PCM has never been updated, so I might take the TL to dealer see what they say.

Does anyone know great indy in Sacramento CA area?

mreducated100

Sparky16

Thanks for the schematic, mreducated.
Do you have your favourite INDY mechanic in Sacramento? Please share with me. Thanks.

Steve

Majofo

swapping them out isn't a big deal (easy diy).. figuring out if that's your real issue is.

let us know if it runs 3k rpm at 75 in 5th.

Sparky16

I think we're talking two different solenoid here.
Code P0977 is for "shift solenoid B", but the schematic referred above is for linear solenoid.

Google search shows this; https://www.google.com/search?q=shif...F%3B1024%3B768


This must be the one, I'm not sure if I need front or top of case. It says TL has 2.
http://www.partsgeek.com/ss/?i=1&ssq...006+TL&x=0&y=0

swoosh

iTrader: (5)

Steve,

sorry I just saw your PM....Maj and MrEducated have you covered here....

also, just an FYI 2500 rpm is high for being in 5th (70 is bam @ 2K rpm) and I think its tooo low for being in 4th (cant confirm since am away from my car at the moment)....

Sparky16

Thanks Swoosh,

It is pretty high to have 2500 RPM @70MPH for 5th gear, must have been at 4th, gas mileage was pretty bad at 25MPG instead of 30.

Did another 3x3 ATF drain & refill with Honda DW-1, now the ATF has some red hue in it, LOL. I'm taking the TL to Nielo Acura tomorrow. Hope they find the answer. Appreciate your posting.

Steve

Majofo

That solenoid you have pictured is correct, but the location you have circled is incorrect. The B solenoids sit under the radiator hoses, above and adjacent from the starter. There are 3 o-rings for each, which also need to be included when replacing. Don't reuse the o-rings. But like I stated, make sure it's the solenoid before replacing them. There are a series of checks including testing the resistance at the pcm and at the sensor that should be done to verify they are at fault. Also, acuraoemparts is usually the cheapest source. It's $29 for each sensor w/ o-rings at aop.

Sparky16

Thanks for your reply.
You're mostly right about the solenoid. TL has 2 identical shift solenoid B, one where you described, another where I marked red(both are numbered #11). I'm not capable of checking to see if they're in fact defective and pretty tough area reach, going to take it to dealer this morning. I did everything I'm capable of doing. Thanks for the help again.

dowikin

Sorry to bump this but did you find a solution to your P0977 Shift solenoid B problem Sparky16?

im having a similar problem and can’t figure it out

pohljm

6 years later and Sparky is still active recently, but you may want to send him a direct message.

dowikin

I tried but being a new member I believe my privileges are restricted

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you do not have permission to access this page. This could be due to one of several reasons:

1. Your user account may not have sufficient privileges to access this page. Are you trying to edit someone else's post, access administrative features or some other privileged system?
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