1995 Grand Prix with transmission problems

1995 GP SE 2 dr., 3100 V6 with 152K, 4T60E transmission. The trans was serviced 3000 miles ago. Fluid level is correct, red with no burned smell. Car is in good condition and has been trouble free for the 3
years I've owned it.
Without warning low gear and 4th gear are gone. The only gears I have left are 2 and 3 and I can only get 2nd if I shift it manually. Put the selector in D and all you get is 3rd. Put the selector in 2nd you get 2nd. No lockup either.
Oh, No SES light.
The only thing I can find wrong so far is the TCC Fuse (15A) is blown and it blows a new one immediately.
The Haynes manual recommends looking for a short in the wiring between TCC fuse and TCC connector. I did that and found all the wires looked good.
Could this be an short in the wiring harness inside the transmission or a solenoid?
Mike T
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Get it scanned on a trans capable scanner, it can check for proper solenoid operation. Also try, disconnecting and connecting main harness connector at the trans, look for corrosion there or a loose connection.

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Thanks Shep;
I already did all the basic easy stuff like look for damage, corrosion, disconnected wiring etc. I also used a test light and multimeter on the wiring harness to try to find a bad wire. No evidence of corrosion at any connection and the harness actually looked real good. No cracks, grease, dirt. I even checked the resistance at each pin on the round plug connection at the transaxle.
I spoke the guy at the Shop that does my trans work. When I took it there a few weeks ago when the problem first appeard they checked it over. Something they plug in under the dash and drive the car around. They found no error codes. They've been square with me before and I have no reason to doubt them.
This is what is such a mystery. Nothing looks wrong yet it's blowing the fuse.
Thanks for the assist.
Anyone else?
Mike T
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You need to assume the tcc solenoid may be shorted, try and find out which wire it is and disconnect it for test purpose, remember the solenoid has constant 12v feed, then the pcm grounds it for operation.

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In the 1994 and later 4T60E, the TCC fuse feeds power to ALL the solenoids in the transaxle. Since none of the shift solenoids are receiving power, in D or OD all you will get is 3rd gear. (For reference, take a look at the schematic on Pg. 12-32 of the Haynes Manual 38010).
Unplug the electrical connector from the fransaxle and try replacing the fuse. If it blows with the transaxle disconnected, then your short is EXTERNAL to the transaxle. If the fuse does NOT blow, then you probably have a wiring short inside the transaxle. You'll have to pull the side cover to get to the wiring to check it out.
I'll bet that the transaxle is mechanically OK - just get the shorted wiring and/or solenoid fixed and you'll be OK.
Regards, Bill Bowen Sacramento, CA
snipped-for-privacy@epix.net wrote:

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Thanks Shep/Bill;
The fuse does not blow with the round plug disconnected from the transaxle. I discovered that on Saturday when I inspected the harness for damage. Good to have my suspision that it may be a shorted TCC Solenoid confirmed.
As far as the general condition of the trans goes it is a little tired anyway, slips a bit on the 1-2 shift and occasionally will not lock up in overdrive. I am going to weigh the cost of a rebuild and the cost of perhaps just replacing the solenoids and internal harness. But probably will opt for a rebuild as the rest of the car is in top condition.
I wanted to solve this fuse issue before spending $1400.00 on a rebuild and finding out the problem was still there.
Mike T
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replying to mjticon, 1BADJ wrote: What was the final outcome? Curious. Have one stuck in 3rd as well. Looking into possible causes/remedies...thx!
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responding to http://www.motorsforum.com/gm/1995-Grand-Prix-with-transmission-problems-17481-.htm 95pontiacgp wrote:
snipped-for-privacy@epix.net wrote:

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im having the kinda same problem i have 95 grand prix with 112k my car starts off in third and wont shift up. only goes in second if down shifted but wont go into first or 4th at all i changed all my fluid and filter. the fuild was perfectly fine. i later found out my f/injn 15a fuse was blown so i changed it. took it for a drive and it went through all the gears fine but then i turned around and it was stuck in third again. the fuse blew again. and i tried it 4 times and it all did the same thing. ive noticed the car is runnin a little funky but seems kinda normal. i dont know what to try replacing or whats blowing my fuse. someone please help.
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