3rd gear only

NomadTW · #1 04-15-2004, 10:40 PM

my 'new' legacy 4eat that i had put into my svx will not shift into any gears other than 3rd (i believe it's 3rd)... it doesn't even try, it just stays in 3rd... slam on the gas... accleerate from 3rd cruise the hwy at 6500rpm 120mph in 3rd cruise the hwy at 60mph 3250rpm in 3rd

any idea what could cause this other than the incompatabilities in tcu?

is it possible some wires are hooked up wrong?

i will be bringing the car to reading despite it's condition

i have no CEL showing on the dash

oab_au · #2 04-15-2004, 11:11 PM

Quote:

Originally posted by NomadTW
my 'new' legacy 4eat that i had put into my svx will not shift into any gears other than 3rd (i believe it's 3rd)... it doesn't even try, it just stays in 3rd... slam on the gas... accleerate from 3rd cruise the hwy at 6500rpm 120mph in 3rd cruise the hwy at 60mph 3250rpm in 3rd

any idea what could cause this other than the incompatabilities in tcu?

is it possible some wires are hooked up wrong?

i will be bringing the car to reading despite it's condition

i have no CEL showing on the dash

The box has gone into failure mode, that's why you only get 3rd, both shift solenoids off. Look for a disconnection between the box and the TCU.

If this has just happened, and it has run ok since it was fitted, then the wires must be connected correctly.

Harvey.

ps have a great time at Reading.

UberRoo · #3 04-16-2004, 02:35 AM

Your TCU is in Limp-home mode. There may be several causes, but the only cause I can think of off the top of my head is that one of the shift solenoids (1 or 2) is dead. Usually this is caused by a loose connection, but it can be caused by a short to ground also. There may be other reasons why the TCU would revert to limp-home mode, but this is the first one on the list.

Don't waste your time until you check for trouble codes.

NomadTW · #4 04-18-2004, 11:04 PM

well while i was at reading i pulled codes from the trans and got errors for duty solenoid A and shift solenoid 2

i mentioned this to randy and it reminded him that the tranny shop mentioned having to do something witht the wiring to make it work

what is the likelyness that the legacy transmission's pins for thes two solenoids on the harnes are switched in position from the ones on the svx?

oab_au · #5 04-19-2004, 05:07 PM

Quote:

Originally posted by NomadTW
well while i was at reading i pulled codes from the trans and got errors for duty solenoid A and shift solenoid 2

i mentioned this to randy and it reminded him that the tranny shop mentioned having to do something witht the wiring to make it work

what is the likelyness that the legacy transmission's pins for thes two solenoids on the harnes are switched in position from the ones on the svx?

Hi there, you did not reply, if this was like this, from the start of the swap, or if it came on after a while,

If the connection was wrong it should have done this, from the start.

If it has just started after a while, then it would, have to be something that has gone wrong since, loose plug, cut wire, wire squashed between something. It could be in the loom from the box, or the loom that runs from the shift lever switch. Does all the shift pisition lights on the dash, follow the lever movement?

If shift solenoid 2 was out only, you would get 3rd and 4th. If solenoid 1. was out, you would get 2nd and 3rd.

No signal, gives 3rd only.

Harvey.

UberRoo · #6 04-19-2004, 10:16 PM

It's possible that you may have a latent code for solenoid A. Perhaps you or someone else has disconnected the dropping resistor beside the battery? In either case, it's almost certainly unrelated to your problem.

The code for solenoid 2 is probably a current code. If the TCU detects a problem with either shift solenoid (1 or 2,) it will shut both of them down completely, leaving you stuck in third gear. I think there are other conditions that will cause this reaction by the TCU, but I don't know what they would be.

I would recommend pulling the plug off of the TCU and testing impedance on the harness for both shift solenoids. (They should be the same.) Test this at the connector on the TCU, as there is another plug below the throttle bodies that may be faulty.

Slightly above the driver's side kick-panel (under the dash near the fuse box) you'll find the TCU. Unplug the black 16-pin connector and orient it so that you are looking at the end of it that actually plugs into the TCU. (Wires going away from you.) Make sure the locking lever on the connector is up. At this point the pins are numbered left to right, top to bottom, one through sixteen.

Using the wiring diagram, measure the impedance of shift solenoids one and two. Measure the resistance between pin ten and fourteen. It should be fairly low. Next measure between pin ten and thirteen. It will probably be infinite (interrupt) or almost none (short.) ...of course it should be the same as pin fourteen, but if there's a problem it won't be.

Pin 10 / Black wire = Ground
Pin 13 / Blue-green wire = Solenoid 2
Pin 14 / Blue-yellow wire = Solenoid 1

(On the TCU picture, I've highlighted the three connectors. You want the blue one. The white highlight is the black ground wire, the green highlight is the blue-green solenoid one wire, and the yellow highlight is the blue-yellow solenoid two wire.)

NomadTW · #7 04-19-2004, 11:50 PM

it has been doing it since i picked it up from the shop

but it did not do it for randy while he had it and it worked when he had it taken out of the shop

i have the resistor pulled so i guess that's what's throwing solenoid A

man i'm gonna need to get a multimeter don't think we have one...

sorry posted late at night

new question tho

if the solenoid is shot it should still have the same resistance correct?
it should only show different resistance if the wiring is bad

NomadTW · #8 04-20-2004, 12:54 PM

ok... tested the resistance of pin 13 to ground and pin 14 to ground both were showing a reading of open ...

then just for kicks tested them against each other... got a reading of 25

should that happen?

i was supposed to test at the connecter on the wires right? not in the tcu connecter

NomadTW · #9 04-20-2004, 01:28 PM

Legacy Wiring Diagram

it looks DIFFERENT

could this explain the problems?

Sonar · #10 04-20-2004, 03:06 PM

Quote:

Originally posted by NomadTW
ok... tested the resistance of pin 13 to ground and pin 14 to ground both were showing a reading of open ...

then just for kicks tested them against each other... got a reading of 25

should that happen?

i was supposed to test at the connecter on the wires right? not in the tcu connecter

This could indicate that the earthpoint is broken.

edit: connector B83 seems interesting ....

/Sonny

UberRoo · #11 04-20-2004, 08:44 PM

Yes, don't test the TCU. You only want to test the connector and wires.

You should be able to read them with a test light, but that'll only tell you:

A) They're good, or they're shorted.
or
B) They're bad, or they're disconnected.

Also, I think you can run 12 volts to the solenoids to test them. You might be able to hear them clicking inside the tranny.

Make sure you have the right pins on the connector. It's damn confusing reading those diagrams, and then comparing them to what's on the car.

As far as getting infinite resistance for either pin 13 or 14 to ground, yet getting a good solid 25 between the two - that should not happen. I might ask, what did you get 25 of? Ohms, Kilo-Ohms? (I'll try to measure mine so you have a baseline resistance to work from.)

You might look under the throttle body for the tranny connectors. There are two of them. One is for the shift lever switch. The other is for the tranny. Check both of them. (I'd separate them and make sure the pins are all intact and clean.) When they remove the tranny, those are the only electrical connectors they touch. If it's a connector, that'll probably be it.

Regarding the Legacy diagram you posted, it appears that the number scheme they use is completely different. This doesn't mean the pinout is different, just the labeling. The picture you gave doesn't show the connector pinout, and I can't quite read the number on the TCU. Looks like "o6," but there are no other "o" anythings. I just can't tell.

NomadTW · #12 04-20-2004, 11:06 PM

here is the rest of that page

i'm going to go check the plugs under the throttle body

is there a ground to chassis anywhere from the trans that they might've disconnected?

i'll re-read the connecter and tell you what the 25 was (haven't really used a multimeter before just went out and bought it)

NomadTW · #13 04-20-2004, 11:06 PM

oops forgot the attachment

Sonar · #14 04-21-2004, 01:19 AM

Quote:

Originally posted by Sonar

This could indicate that the earthpoint is broken.

edit: connector B83 seems interesting ....

/Sonny

Nope, sorry, on your new pic I can see that it could not be B83 !

The solenoids seem to have their "own" earthpoint.

The reason I think it could be a broken earthpoint is that if both solenoids are tied together by earth, but not connected to the cars "ground", you will get connection between the solenoids "positive" connectors (but the double resistance) , but you would NOT get a connection to the cars ground (earth).

...duuh..was that understandable, my english is not that good...

And the figure of 25 , if it was ohm and BOTH solenoids, 1 sol. has 12-13 ohm, that gives a current (w. 14.4V) of slighly over 1 amp. witch seems reasonable to me.

/Sonny

NomadTW · #15 04-21-2004, 01:28 AM

interesting news...

first off what i was measureing in i'm not sure but i have a generel electric digital multimeter model GE2524 and i had the selector set to 2000... whatever that means

went under the TB and pushed all the plugs i could find all were secure

then i noticed what seemed to be a ground wire coming from the trans to the firewall with a plug connector in between...

the wire was bare and exposed on the transmission side of the plug, so i decided to take the multimeter to that bare wire and to a bolt in the firewall just to see.... OPEN full resistance...

so does this mean that that connection is what is causing everythign to go awry?