1995 Q45 "Transmission Malfunction" Anybody ever had this issue?

Post by **barts71rs** » Tue Jul 25, 2006 5:01 pm

I have a 1995 Q45 and for some reason it has started shifting a little hard and a warning message in the lower right hand display in the cluster says "Transmission Malfunction". I hope this is an external trans problem(sensor,etc...) If anyone out there has ever seen this message and knows a direction to point me in I would appreciate it. Thanks

Post by **elwesso** » Tue Jul 25, 2006 5:45 pm

welcome to NICO bart... im gonna move this to the online mechanic...

put your car in diagnostic mode and we can go from there.. to set the car into diagnostic mode, do this.....

ALL of this is done engine not running.

1. make sure the temp gauge is in the middle (the test WILL NOT work if the engine is cold)2. Put the car in D and set the parking brake (so you dont go rolling). You can turn the key on, shift to D, and turn the key back off.3. While turning the key to ON, hold the trip odometer reset thing to the right (clockwise)... The display should come up with AT CHECK.. If it does not, turn the car off and try it the other way... Regardless, AT check will come on by turning the key on and turning that knob at the same time, i jsut cant remember which way.4. Once AT check is on. shift to 3rd gear, and press the gas all the way down and release it.... Then shift to 2nd, and then to 1st gear, nad then press the gas all the way down...5. The display will pop up the codes... post your codes up and ill tell you what they mean!!

Post by **Q45tech** » Wed Jul 26, 2006 4:39 am

Important that we know transmission mileage [orginal or replacement] and codes to evaluate.

Most 94-96 last 150,000+ miles if properly maintained and fluid replaced every 30,000 miles. Even those that never get fluid replacement make it to 100k

Post by **barts71rs** » Thu Jul 27, 2006 12:27 pm

Ok I did the check and everything seemed to work the way you stated. You turn the trip counter - counter-clockwise. the only code I get is the letter B other than that it just sits there with the cursor flashing. I sat there for a while and nothing else happened. I really appreciate your help on this. Thanks alot and let me know, Bart Bishop

Post by **barts71rs** » Thu Jul 27, 2006 12:29 pm

Hello my car has 129,000 miles on it and it is the original transmission. The matience has been performed by the dealer and trans services where performed. It runs excellent and has been a great car. The transmission comes up with the code : B. Thanks for any help, Bart

Post by **maxnix** » Thu Jul 27, 2006 2:13 pm

barts71rs wrote: The matience has been performed by the dealer and trans services where performed.

Could you itemize specifically what the services performed included? Dealer standards vary. Most don't perform a mechanical fluid exchange with a pan drop and filter replacement. Some don't even change the differential fluid every 30K.

Post by **elwesso** » Thu Jul 27, 2006 2:22 pm

Well this makes sense.. The code is for the LINE PRESSURE SOLENOID... clear the codes and make sure it comes back.....

in the mean time, check the resistance of the line pressure solenoid. Get to the TCU, probe the number 1 pin on the TCU (very top right pin, orange wire), and test it with your multimeter to ground, shoudl be about 2.5-5 ohms, however ive found mine to be about 4-4.5 ohms!!!

If the resistance check fails, then the solenoid is probably bad..... You have to buy it in a 4 pack solenoid kit... that includes the line pressure solenoid, overrun clutch solenoid, and shift solenoids A and B... Cost is about $150 and labor is probably 2 hours or so, nothing bad.... if you want to DIY, we can assist you!

Post by **barts71rs** » Thu Jul 27, 2006 3:52 pm

Boy, That is great news!!! I will have to do this myself because we only have one Infiniti dealer here in town and they take you to the cleaners. They wanted $125.00 to just run diagnostics on it. Thank you so much for the info. Any assistance you can give on the repair would be very much appreciated because as of now I dont even know where to start. I love this car and was hoping it didnt need a transmission. Where is the plug to probe to get the ohm reading, I have an OTC Multi Meter. Also how do you reset the cars system to clear the code. Like I said it is shifting rather quick and you can feel it more than you used to be able to. Are the parts dealer parts or can you get them aftermarket and where? Thanks again for your time,Bart

Post by **elwesso** » Thu Jul 27, 2006 3:59 pm

Bart... Get your parts from Joe.. his contact information is in my signature, tell him you know Wes.....

Anyway about the repair... Its not too bad... Ill try and outline the steps here a little bit.. Basically all you do is remove the trans pan and remove the valve body.. To get access to the front bolts on the trans pan, just bend the cooler lines a little bit out of the way... Once you have the trans pan off, your going to want to remove the filter and the terminal cord assy, and the pipes going to the torque converter solenoid.. Then you can take the bolts out of the valve body, drop the valve body, and the solenoids are sitting there on top...

You WILL want the FSM for that, if you have it, its got a great section on how to rmove this... If you dont, fire me an email and ill hoook you up!!! I see your not too far away from me, im up a little bit north of Indianapolis and Ive been down to Louisville a few times for meets.

Post by **barts71rs** » Thu Jul 27, 2006 4:09 pm

Hey Wes, I dont have the FSM(manual) so I would appreciate your info. Not sure how to email you directly. My email address is [email protected]. This forum is incredible im hooked! I will get pictures of my car and post them(its pretty sharp). I live in St. Matthews in louisville. I will contact Joe and get the parts. Thanks again

Post by **elwesso** » Thu Jul 27, 2006 4:15 pm

bart, ill send you an email, but for future reference you can just click on my screen name and it will bring my profile up, and my email addy is right there.

BTW the TCU which is what you need to check the line pressure solenoid resistance from is behind the drivers side kick panel.....

Post by **barts71rs** » Mon Jul 31, 2006 11:38 am

Hello Wes, I replaced the solenoids this weekend. The car still seems to shift harder than normal. I havent been able to figure out how to reset the computer so the "transmission malfunction" message is still there. How do you reset the message(codes)? Could the car be in some kind of "failsafe" mode? I really dont know much about these cars except that I love it and hope that it doesnt need a trans replacement. The transmission shifts when it is supposed to just from 1st to 2nd its a little quick and stiff. I would like to try and reset the computer and see if it comes back on I could be to critical on the shifting because I am aware of it now. So like I said info on resetting the codes would be my next step or if its in the manual if you know what section because I cant find it. Thanks again,Bart

Post by **MarriedTo94Q45t** » Wed Jan 24, 2007 7:57 pm

Bart,

I am even newer than you are to the NICO club. I have a 1994 Q45t and when it is cold it does not shift from 1st to 2nd until the tranny warms up. And sometimes it happens when it is warm. Did replacing the solenoids fix your problem? Looks like I will have to do the same thing. I was told it might be a sensor somewhere. This has been going on for 10,000 miles for me but has gotten worse recently. I have 80,000 miles on my car, and have owned it for 10 years.

Post by **maxnix** » Thu Jan 25, 2007 4:48 am

Since there is so little detailed maintenance history posted by the owners in this thread, I would reommend reading the past posts on what constitutes a proper mechanical fluid replacement, and the importance of including the pan drop and filter replacemnt. If this filter is never replaced, even if it looks good to the naked eye, it can be clogged enough to impede flow and all the new solenoids and fluid in the world will not help.

Married to Q45t, welcome in and you have certainly found the right place to come to an understanding with your wife.

Be sure to read all of Q45tech's posts. And follow the links.
Modified by maxnix at 7:00 AM 2/26/2007

Post by **sdkhalsa** » Thu Jan 25, 2007 5:30 am

I have a 94' Q with 107K on it and previously had a hard shifting problem. This seemed to be more the case when the car had warmed-up. What I found was a bad temp. sensor in the transmission. The system is designed to provide harder shifts when cold. My solution was to put a variable resistor(pot) which I set to an intermediate value just below the transmission control unit. This saved me the expense of having the old sensor replaced. Here in Arizona, because of the somewhat constant temperature, this solution works very well. If this sounds of interest to you, I can dredge up the details from a previous posting. By the way, no codes were put out even though my temp. sensor was 100% dead.

Post by **msogun** » Fri Feb 23, 2007 3:50 am

Which one is better for a Q45a Transmission. Rebuild or Replace?

Post by **Rex** » Fri Feb 23, 2007 4:11 am

msogun wrote:Which one is better for a Q45a Transmission. Rebuild or Replace?

Speaking from experience, replace with an OEM (or Level 10) reman.

Post by **Q45tech** » Fri Feb 23, 2007 4:34 am

By now I would expect that almost every 90-96 has had a replacement transmission 11-12 years is way beyond average life. I'm on #3 [installed 2002] and it has 100k now.

It is combo of miles and YEARS of use.............low miles usually means city driving which requires more SHIFTS PER MILE vs driving 8 hours on an interstate.

The dealers use Nissan/Jatco factory remanufacturered units which are excellent and typically last 5-7 years [60,000 miles +] even though the have a 12k warranty like all replacement parts.

There are thousands of tranny shops in US and only one factory reman facility.

To sell for less most tranny shops just throw in a $300 kit and do the minimal necessary. While the factory actually rebuilds and replaces TC and valve body.

Don't be confused in what you are getting for $2,000 vs $4,000.

Used old trannies are just that used and old sitting degraded year after year.

I have been lucky to buy wrecks and junks where the tranny was recently replaced then something else failed.

When someone is buying a used car I always remind to have available the $3,000 [a reman will cost] plus another $3,000 to fix all the neglected repairs they don't know about.........

Buying a $4,000 used car just means you need $6,000 more soon, most people cannot fathom this until it happens!

Something BMW/MB/Audi owners have learned.

Post by **sdkhalsa** » Fri Feb 23, 2007 5:05 am

I had similar sympoms with my 94' Q at 100K. The problem was a defective temperature sensor in transmission. This can be diagnosed by taking a voltage reading on the relevant pins on the TCU(side panel, driver side). What I did was cut-out the temp. sensor and replaced with a variable resistor(trim pot) set at a mid-range value. Works great. The force of the gear engagement is increased when the transmission is cold and reduced when hot. If you need further info. let me know.

Post by **AZhitman** » Fri Feb 23, 2007 6:07 am

Great thread!

Mine had the same issue as well, was traced to a bad throttle position sensor.

Elwesso and Tech have done a GREAT job in this thread, good info all around!!!

Post by **msogun** » Mon Feb 26, 2007 4:39 am

sdkhalsa,Could you give me more information as to how to do this. Is the sensor to replace inside the transmission? Is it hard to do. Or should I just replace my TCU? My transmission won't go to Drive until it is warm up. I normally put it in 3 and then change to Drive in about 2-3 minutes.

Post by **maxnix** » Mon Feb 26, 2007 4:58 am

msogun wrote: I normally put it in 3 and then change to Drive in about 2-3 minutes.

It's working as designed, then. Operating temperature is.....uh....when it should be operational.

This is an interesting thread, but I wonder if the fix is just a palliative masking a required repair?

Post by **sdkhalsa** » Mon Feb 26, 2007 5:08 am

The problem I had was that once the car had thoroughly warmed-up the shifts would become very harsh. It was not a situation of delayed shifts. Let me scrounge together the pin numbers later today or early tomorrow. The test is very easy to do, only requiring a digital voltmeter. I would hold off on the TCU a bit. Meanwhile, if you are in the mood for crawling around under the transmission, an ohm reading can we taken at the temp. sensor connector.

Post by **Q45tech** » Mon Feb 26, 2007 6:55 am

Normally one uses the Consult to view the fluid temperature sensor operation along with 35 other parameters.

If a temp sensor fails it was destroyed by acidic ATF from lack of changes unless [rarely the engine overheated and transferred heat to the AT case].

We see this after severe overheats from owners not changing oil, coolant, and ATF immediately.

Read the voltage at pin 33 on TCU at 68F ~~ 1.5 v dropping to 0.5 volts at 176F.

The transmission is not designed to function except in an emergency until warmed to 68F..................failure to allow adequate warmup will stress and decrease usable life....................one of the reasons driveline warranty is only 70k................crank and go abusive drivers.

All fully explained in FSM

Post by **AZhitman** » Mon Feb 26, 2007 7:21 am

Q45tech wrote:crank and go abusive drivers.

Which, according to Webster's = SPOUSE.

Post by **sdkhalsa** » Tue Feb 27, 2007 5:13 am

Here is my original post with the specs.concerning the test of the transmission temp. sensor. It uses the same values as just mentioned by Q45tech: zerothread?id=173956

1995 Q45 "Transmission Malfunction" Anybody ever had this issue?

1995 Q45 "Transmission Malfunction" Anybody ever had this issue?

Re: 1995 Q45 "Transmission Malfunction" Anybody ever had this issue? (barts71rs)

Re: 1995 Q45 "Transmission Malfunction" Anybody ever had this issue? (elwesso)

Re: 1995 Q45 "Transmission Malfunction" Anybody ever had this issue? (elwesso)

Re: 1995 Q45 "Transmission Malfunction" Anybody ever had this issue? (Q45tech)

Re: 1995 Q45 "Transmission Malfunction" Anybody ever had this issue? (barts71rs)

Re: 1995 Q45 "Transmission Malfunction" Anybody ever had this issue? (maxnix)

Re: 1995 Q45 "Transmission Malfunction" Anybody ever had this issue? (elwesso)

Re: 1995 Q45 "Transmission Malfunction" Anybody ever had this issue? (barts71rs)

Re: 1995 Q45 "Transmission Malfunction" Anybody ever had this issue? (elwesso)

Re: 1995 Q45 "Transmission Malfunction" Anybody ever had this issue? (barts71rs)

Re: 1995 Q45 "Transmission Malfunction" Anybody ever had this issue? (elwesso)

Re: 1995 Q45 "Transmission Malfunction" Anybody ever had this issue? (barts71rs)

Re: 1995 Q45 "Transmission Malfunction" Anybody ever had this issue? (barts71rs)

Re: 1995 Q45 "Transmission Malfunction" Anybody ever had this issue? (barts71rs)

Re: 1995 Q45 "Transmission Malfunction" Anybody ever had this issue? (sdkhalsa)

Re: 1995 Q45 "Transmission Malfunction" Anybody ever had this issue? (msogun)

Re: 1995 Q45 "Transmission Malfunction" Anybody ever had this issue? (msogun)

Re: 1995 Q45 "Transmission Malfunction" Anybody ever had this issue? (Q45tech)

Re: 1995 Q45 "Transmission Malfunction" Anybody ever had this issue? (sdkhalsa)

Re: 1995 Q45 "Transmission Malfunction" Anybody ever had this issue? (msogun)

Re: 1995 Q45 "Transmission Malfunction" Anybody ever had this issue? (maxnix)

Re: 1995 Q45 "Transmission Malfunction" Anybody ever had this issue? (sdkhalsa)

Re: 1995 Q45 "Transmission Malfunction" Anybody ever had this issue? (Q45tech)

Re: 1995 Q45 "Transmission Malfunction" Anybody ever had this issue? (AZhitman)

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