|
|
toyota A340 trans wont go into over drive
|
|
|
| |
|
|
peculiarwheel
Novice
Feb 19, 2013, 10:29 PM
Post #1 of 12
(3445 views)
|
|
toyota A340 trans wont go into over drive
|
Sign In
|
|
I have a 2002 Toyota Sequoia truck with four wheel drive. My trans was destroyed when the OD bearing went. I rebuilt the trans and upgraded the OD Planet with the improved one in the 03 and later trucks. The trans works but it wont shift into OD...and it does very hard shifts from 1st to 2nd gear unless Im very easy on the gas. It also goes into gear kind of hard when I shift from park. I get the error code that indicates my speed sensor isn't working. This is the one that towards the front of the trans (just behind the bell housing).
I bench tested the sensor and it checked good...but problem remain
I replaced the sensor and problem remain
I checked the harness for obvious opens and cant spot any. I didnt do an end to end continuity test because I cant get a prob at the computer plug end.
I know the computer could be bad or the harness....but i dont believe in coincidences. They were working before the trans blew up. I dont know how disconnecting the connectors of the harness could damage the computer. I have a manual override to turn OD off that is at the end of the column shifter. clicking on it doesnt fix the issue. and again...it worked right before the rebuild.
As for the rebuild....I can't imagine what I could have done wrong to make it not send a signal to the magnet at the end of the sensor. In the area the sensor is located....it appears to be reading the fins off of the OD direct drum. How can that be put in improperly? What other assembly error might I have made? Any one know this trans?
I'm stomped as to what it could be. Do I need to reset the computer? Is there an easy way to test harness?
Any help would be appreciate. Thanks
|
|
| |
|
|
nickwarner
Veteran
/ Moderator
Feb 20, 2013, 7:01 PM
Post #2 of 12
(3398 views)
|
|
Re: toyota A340 trans wont go into over drive
|
Sign In
|
|
You need to hook up a scan tool that can view data and watch the data pid for your speed. If you have a GPS to compare the reading to that might help. But you're looking for and erratic reading.
|
|
| |
|
|
peculiarwheel
Novice
Feb 20, 2013, 9:40 PM
Post #3 of 12
(3386 views)
|
|
Re: toyota A340 trans wont go into over drive
|
Sign In
|
|
ok....you lost me. What is a GPS as it relates to a trans? And what would all this tell me? If my computer is bad or not....or what?
Are you assuming I dont have a mechanical problem with the trans?
Thanks
|
|
| |
|
|
Hammer Time
Ultimate Carjunky
/ Moderator
Feb 21, 2013, 5:57 AM
Post #4 of 12
(3378 views)
|
|
Re: toyota A340 trans wont go into over drive
|
Sign In
|
|
A GPS carried in the truck will give you a land speed to compare with the truck speedometer reading.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.
|
|
| |
|
|
peculiarwheel
Novice
Feb 21, 2013, 6:08 AM
Post #5 of 12
(3374 views)
|
|
Re: toyota A340 trans wont go into over drive
|
Sign In
|
|
Ok...Im just not understanding where you guys are going with this. Will the scanner tell me if the computer is picking up the signal? If so....what does that have to do with GPS?
And what does GPS has to do with the speed the transmission is spinning (the reason for the input shaft speed sensor....the one Im referring to in this post)? I didnt even know my 02 Sequoia had any type of gps.
So if the computer scanner shows erratic readings...what would that point to? The harness?
Does anyone think this is a mechanical problem?
Thanks
|
|
| |
|
|
nickwarner
Veteran
/ Moderator
Feb 21, 2013, 4:36 PM
Post #6 of 12
(3363 views)
|
|
Re: toyota A340 trans wont go into over drive
|
Sign In
|
|
You're getting an error code for your speed signal right? So this trans isn't going to be commanded to go into overdrive if it doesn't see the right signal. As HT already clarified, the idea of using a GPS is to compare the reading you are getting of road speed to a second source of information not related to the vehicle. Either that or do 80 in front of cop and see what he says came up on radar.
You need a scan tool that can view live datastreams to see what the reading is from your speed sensor. It might be glitching badly enough that you can catch it with the scanner, if not an oscilloscope might be required.
If you do get erratic readings, they would then need to be troubleshooted to determine the cause. There are a lot of variables here. You need to do some testing to narrow down where this issue is coming from.
|
|
| |
|
|
Discretesignals
Ultimate Carjunky
/ Moderator
Feb 21, 2013, 5:19 PM
Post #7 of 12
(3361 views)
|
|
Re: toyota A340 trans wont go into over drive
|
Sign In
|
|
What is the trouble code number? The one that reads off the direct drum isn't the one used for determining vehicle speed.
Since we volunteer our time and knowledge, we ask for you to please follow up when a problem is resolved.
(This post was edited by Discretesignals on Feb 21, 2013, 5:22 PM)
|
|
| |
|
|
peculiarwheel
Novice
Feb 24, 2013, 9:32 PM
Post #8 of 12
(3334 views)
|
|
Re: toyota A340 trans wont go into over drive
|
Sign In
|
|
Thanks for the replies guys.
I'm still confused about the vehicle speed perspective as to my problem. Either Im just missing it or I wasnt clear before. When I say speed I'm referring to the speed of the spinning input shaft on the transmission.
My fault code is P0715 or may be P0717..I don't recall off the top of my head...but it is definitely one of these two. When you look up their meaning you get:
P0715 Input/Turbine Speed Sensor Circuit Malfunction
and
P0717 Input/Turbine Speed Sensor Circuit No Signal
"Input" is referring to the input shaft. Also...the toyota service manual guides you to the transmission and the harness for that code.
If I'm correct...then what troubles me is HOW the sensor or harness or computer all of a sudden go bad? And if they are not bad...what could cause that "mis-code"?
I like the idea of a scanner that can verify what the computer see. I'm talking it in to a trans shop this week...so maybe they will have that ability. but if its something simple that I can do....I prefer that.
|
|
| |
|
|
Discretesignals
Ultimate Carjunky
/ Moderator
Feb 25, 2013, 6:04 AM
Post #9 of 12
(3319 views)
|
|
Re: toyota A340 trans wont go into over drive
|
Sign In
|
|
Looking at the speed sensor information using a scan tool is a good idea to see if the PCM is even getting the signal. If the PCM isn't seeing the signal from the sensor, either the circuit is open or the signal is corrupted. If you have a graphing multimeter or lab scope you could see the actual signal and tell if there is a problem. It is best to get the signal at the PCM's connector.
Did you replace the drum during your overhaul?
Since we volunteer our time and knowledge, we ask for you to please follow up when a problem is resolved.
|
|
| |
|
|
peculiarwheel
Novice
Feb 25, 2013, 11:01 PM
Post #10 of 12
(3295 views)
|
|
Re: toyota A340 trans wont go into over drive
|
Sign In
|
|
Ok...then a shop will have to check that for me.
My replacement od assembly included the entire thing..spiral gears...bearings...and drum. What concerned me about the drum is that I can look at the original one and cant fathom how I could have made a mechanical error. if it is the harness...then i must have cracked a dry brittle wire.
|
|
| |
|
|
Discretesignals
Ultimate Carjunky
/ Moderator
Feb 26, 2013, 5:56 AM
Post #11 of 12
(3288 views)
|
|
Re: toyota A340 trans wont go into over drive
|
Sign In
|
|
I guess you'll have to wait and see what the shop comes up with as for the PCM actually getting a signal or not.
If the wiring is good and the sensor is good, the only thing that I can think of is the drum is somehow different. Would be rare for the PCM to be the culprit.
What I mean by the drum being different is the interrupters on the drum being physically different causing the speed sensor to generate a signal that the PCM doesn't recognize.
Since we volunteer our time and knowledge, we ask for you to please follow up when a problem is resolved.
|
|
| |
|
|
peculiarwheel
Novice
Feb 26, 2013, 7:21 PM
Post #12 of 12
(3270 views)
|
|
Re: toyota A340 trans wont go into over drive
|
Sign In
|
|
unless I'm looking at the wrong thing or something...but the interrupters are the fins that the clutch disks tabs slide down into....so the spacing has to be the same. The fins have holes in them in varying spots...but I suspect that is only for lubrication of the friction disks.
We'll see what the shop comes up with.
Thanks guys.
|
|
| |
|
Auto Repair Home
SEARCH
WHO'S 
LOG 
2011 Dodge Nitro OBD scanner seems to drain battery in 10-20 minutes
Grounding Cable, 2017 Jeep Renegade Trailhawk
equipment
Howdy
