Location of a transmission temp senso

[Azbella]

Hi,
I have a 1993 gmc 2500 suburban 4x4 5.7l auto tranny.

I had ran the codes as it was acting "off." One of the codes
Was for the transmission temp sensor. No problem. However,
No one we know is able to tell us where it is located and I am unable to find that info
Online. Would anyone be able to tell me where to look
For this elusive part? My husband is convinced we purchased a defective part because he can see it but unable to find the one we need to replace.
Gentlemen, please assist me before my car drives my husband batty.
Thanks in advance

 

[THEFERMANATOR]

It is part of the pressure manifold switch.

 

[Azbella]

It is part of the pressure manifold switch.

Okay, this may be a dumb question, but where is that exactly located?
I love my husband, but this is becoming the never ending project and I would like my car soon as school starts next week.
Thank you in advance.

 

[THEFERMANATOR]

It's the switch mounted inside the trans pan. It bolts onto the valve body and has the wide plug on it. It's not that expensive of a part, but with the early 91-93 trucks the more common problem is the trans bulkhead connector if it hasn't been upgraded.

 

[WarWagon]

Quick fix is to unplug that connector and use electrical contact cleaner on it to clean the oil off. It will need a long term fix eventually.

 

[Azbella]

Thank you both for the valuable information. We had to purchase the interior/exterior wire harness for the upgrade. Once it was figured out with your help, it was smooth as snot. Thanks again!!!

 

[billyg38120]

Hello Azbella,
I am afraid you have MISLEAD. The Trans Temp Sensor is NOT a part of the Pressure Switch Manifold Switch Assembly. The Actual sensor is part of the INTERNAL Transmission wiring harness. It has a small two pin connector and is zipped tied to the harness. (The 4L60/65/70-E had IT'S Trans TEmp Sensr as part of the Pres Switch Manifold as did the 4T65E GM Trans.
Now if you have a 1993 with a TFT (Trans Fluid Temp) Code I would look close at the Trans Pass through connector which is notorious for electrical failures causing numerous codes. As above suggested to remove the Torx screw that hold the connector together, clean it with brake clean and let it dry, reconnect it. If the connector has trans fluid leaking, I would suggest to replace it. Well to do this you MUST install / splice in a new vehicle side harness and replace the Internal Trans harness. The Pass Through connector is Updated and will not leak or fail like the 91-93 ones did. The internal harness will most likely have a NEW TRANS TEMP SENSOR attached or zip tied to the internal harness. ()The Trans temp sensor just kinda hangs around in the pan. This is "design intent" as the temp of the fluid will even out within a minute or two.
If this was my trans, I would replace the A and B Shift Solenoid. There were design changes and Ball Seat material improvements made. The reason the B sol fails the most is the B sol spends the most time in the "OFF" mode where the ball is "exhausting" fluid and the fluid causes the ball to beat the seat egg shaped.
Have Fun and be careful who you listen to.
Trans Star has these parts at a Reasonable price and are Delco.

 

[Azbella]

Billyg-
We replaced both interior and exterior tranny wire harnesses. Now we are now pulling codes regarding solenoid a and b. The tranny is a 4l80e automatic.
Where will be be able to locate the 2 solenoids? Plus, since we have replaced both harnesses with the new TTS, it still throws that code. Any suggestions?
My husband is a jeep man with manual trannies and this is his first A/T to work on.
Thanks in advance

 

[THEFERMANATOR]

Billyg-
We replaced both interior and exterior tranny wire harnesses. Now we are now pulling codes regarding solenoid a and b. The tranny is a 4l80e automatic.
Where will be be able to locate the 2 solenoids? Plus, since we have replaced both harnesses with the new TTS, it still throws that code. Any suggestions?
My husband is a jeep man with manual trannies and this is his first A/T to work on.
Thanks in advance

Start checking the wiring harness that goes up over the trans and to the PCM. I seen one before where cow manure had gotten down into the plastic loom and rotted out the the wiring inside of it and caused all kinds of weird issues. The harness looked fine until I pulled the plastic covering off, then it all crumbled in my hands.

 

[billyg38120]

Azbella,
I take "pulling the codes" means you are requesting the PCM/TCM for diag code to blink out or through a scan tool. With this in mind, and you still are having the TFT (Trans Fluid Temp) code, I would suggest you make sure the connector is "CLOCKED" correctly and fully plugged in all the way. (I've heard of this before when a new set up was installed and the connector was 180 degrees off. The tech didn't drive it to see if it shifted or had other codes.)
One MORE thing to keep in mind, those years had a problem with the Ignition Switch (Electrical switch) failing causing Sol A, B and TCC codes. The diagnostic, inside the computer looks for 12 volts, abouts, when the Solenoid is in the OFF mode. If it senses a Low volt it starts a counter and counts to about 2 to 5 seconds and the Code is logged into memory.
I would insure the connector clocked right and plugged in fully. If you pull the connector off, look for pins bent over. Straighten them out and try to connect the connector in using the slots internally on the connectors. If you look at both you'll see what I am saying. Watch out for the lack of 12 volts at the Solenoid feed. In some cases you can use a test light connected to your vehicle Trans Fuse and drive it to find when it will fail. IT usually is the Ignition Sw if this happens But many things happen where one can't see all.
Good Luck and I hope it helps save ya some doe!!!!

 

[Azbella]

Thanks for the help. Gave hubby the info and he decided to replace the sensors. Said he would rather do it now with everything disassembled than later on. Oh well.

 

[NVW]

Billyg-
We replaced both interior and exterior tranny wire harnesses. Now we are now pulling codes regarding solenoid a and b. The tranny is a 4l80e automatic.
Where will be be able to locate the 2 solenoids? Plus, since we have replaced both harnesses with the new TTS, it still throws that code. Any suggestions?
My husband is a jeep man with manual trannies and this is his first A/T to work on.
Thanks in advance

http://www.electricaladvantage.net/4l80esolenoidmasterkitwinternalharness.aspx

This may be too late for you, I used this kit and the parts were AC Delco.

 

[billyg38120]

http://www.electricaladvantage.net/4l80esolenoidmasterkitwinternalharness.aspx

This may be too late for you, I used this kit and the parts were AC Delco.

Hello,
I didn't know if this place so THANK YOU for sending this to me. I always just used Transtar or another supplier.

Keep in mind about the Ignition Switch going Open on some pins and this caused Trans electrical codes.

I would tell your husband if y'all wanna keep this truck, I'd drop the trans oil pan once a year if ya drive it. I don't replace the filter, I just pull it off
allow it to drain, wash the bottom of the trans with a can of Brake Clean, re-install the filter and the wiped out clean pan. Fill it with Dex 3 and GO!!
(The reason I don't replace the filter is this: The OEM filter begins life filtering 160 microns. It's target is 25 to 40 microns for it's life and as the new trans breaks in, as they say, this sediment collects and closes the fiber to it's target. If I replaced my filter and something started to break apart, the new filter would allow MUCH larger particles to pass through and LODGE into the PRESSURE REG SPARING Causing the pressure to go out of control. So I elect NOT to replace it and a YEARLY pan inspect and fluid renew is best. That's my (and others at the Proving Grounds) opinion. For what it's worth.