Having a transmission problem with my 1993 AWD Previa automatic transmission. Will not shift into any gears, driving along the road, other than 1st and reverse. Manual shifting the gear shift doesn't do anything. Dash gear indicator lights, drive and 1st, are on even before the gear shift is moved to those gears. Any suggestions?
Thanks!
I'm not a transmission guy, but I do know that these transmissions are electrically shifted. There are solenoids in the transmission that shift gears based on electronic inputs from the ECU. Due to the indicator light issue, I'd look in that direction before blaming the transmission. I'd be very suspicious of the ECU (under the driver's seat). Sometimes you can get these cheap on eBay (like under $50). If you can find a cheap one, it might be worth a shot swapping it out before taking it in and spending the big bucks (may or may not work.........just a suggestion). Tim
Thanks for the reply Tim, I suspected the same thing and already swapped the ECU. Didn't make any difference. I also changed the Throttle Position Sensor (TPS) connector. I read in another forum that the wires sometimes break inside the connector, again no change. It does seem to be electrical and not transmission as such.
Here's what I know: The ECU controls transmission shifting. It gets inputs from the TPS to help it determine shift points. If the TPS or it's wiring is faulty, the ECU will still still shift through all gears, it simply will default to standard shift points (no kick-down to lower gears during instances of full throttle). By swapping ECU's you have at least ruled that out as not being the problem. That only leaves the wire harness or the transmission itself. Follow the path of the wire harness and check it for any signs of physical damage. Also a good idea to disconnect all connectors and visually inspect for water infiltration, corrosion, and/or burned or otherwise damaged pins. If all this looks good, then I see a visit to a transmission shop in your future. Good luck. Tim
Hey everyone,
I'm having some real van troubles right now. I'v been getting my van into tip-top shape and then but my battery in backwards, which blew a lot of fuses and the ECU. I replaced the ECU and the fuses/fuseable links that blew, and now the van starts and idles great, revs up nicely, but when I put it into gear I get some really bad slipping from the transmission. It lurches and crawls and never really wants to move.
I think (and hope) my transmission is just fine, I had no transmission problems of note before this electrical problem. I had also changed my transmission fluid and filter, but refilled it a little over 2 quarts of fluid. Can someone give me some clues as to where I might start debugging?
Is it possible for an electrical problem to have such harsh effects on my transmission function?
sounds like there isn't enough tranny fluid ....even though you put in two quarts......check it when it is warm and running
Thanks NikiFix,
Sure enough, a little more transmission fluid and my problems seem to have disappeared. I was gun shy with the amount of tranny fluid because I have read having too much can cause problems itself.
Van seems to be operable once again thank goodness. Now my only problems are I am getting a parking brake light and battery charge light on my dash. My battery is new and charged, my alternator is new, I seem to be getting good power from the alternator while the car is running (around 14.3). Any idea why I would get these two lights?
Thanks
Oh and I also have a new (used but seemingly working) ECU.
does the voltage drop under load ie lights and heater fan......I know it is a new alternator....but maybe defective diode.......was the alternator installed before the battery install defect?
I thought there was a problem with my 95 previa because it would start but would not move in gears. I had checked the transmission fluid a couple weeks before and it was fine. When I went to look when it was giving the problems I found that the transmission fluid was empty and that is why it did not want to move. I put some transmission stop leak and also 2 quarts of transmission fluid and let it idle for 20 minutes and it started working in the gears again and it would move reverse and forward.
Originally Posted by firstclass
I need help with my previa 95 transmission. It stop working and would not drive. After I saw the fluid was gone after I had checked 4 weeks ago and it was fine. I added fluid and when I sput the gear in drive it went forward also I put gear in reverse and it went in reverse. The next day it doesn't want to reverse anymore. I put some lucas transmission repair in there and that is what got it driving as well as some dexron 6 and also maxlife transfluid. So I don't know why it doesn't want to drive in reverse. I haven't moved it since I saw the reverse doesn't work. I put it in reverse and the gear doesn't catch for it to move. I disconnected the negative on the battery to reset the computer to see if that helps by reseting some codes. Also I checked the trans fluid after putting some new fluid in there and the color is dark reddish brown which means the fluid is bad. Can anyone help cause I don't think I should have to buy a whole new transmission for this because it cannot work in reverse.
I drove the previa around in drive and after the transmission warmed up the reverse started to work again.
Sometimes the gears will not work if the fluid is too thick. The lucas stop slips autotrans fluid is thick and that might have locked up the gears until I was able to get it driving in forward for awhile and the transmission warmed up.
Dont overfill the tranny!
Its measured in pints not quarts at the dip stick quite unlike the oil dipstick is measured in quart.. Tranny problems are a beast.
drop the pan and clean or replace the filter( its metal and just a screen but it collects allot of gunk! Easy to clean... Get a look at whats really going on down there.
Reply With Quote
