I had a code 700 when I diagnose my 94 GMC Sierra. That is a transmission control unit problem. What's the best and cheapest way to fix it. can I do it myself?

Asked by Feb 19, 2014 at 01:47 PM about the 1994 GMC Sierra 1500

Question type: Maintenance & Repair

I was going 65 70 on the freeway
When I noticed I smelt burning wires.
the truck then kind of held back
power while my foot was still on the
gas . it does this every now and then
feels like its locking up on me. tell me
what's going on and what can I do?

2 Answers

10,375

Well find the burnt wires first. The '94's have a ECM to run the TBI engine and a separate TCU to control the 4L60e. The TCU is located on the drivers side inner fender. Inspect the wiring. Follow the large harness back to the tranny plug. It may be a good idea to drain your tranny fluid to see what conditon the fluid is in. Also inspect the shift solenoids and wiring on the valve body.

10,375

If the wiring looks good you could try replacing the TCU. They are very cheap at the wreckers. Just make sure it's pulled from a 1/2 ton gas with a 4L60e ('93-94). Larger trucks and the 454ss used the 4L80e and the controller is different.

Your Answer

Add photo

Related Questions

Search GMC Sierra 1500 Questions

GMC Sierra 1500 Experts

#1 dragonflyoffshore
dragonflyoffshore
Reputation 5,230
#2 John Saffrahn
John Saffrahn
Reputation 3,640
#3 Glenn Clingenpeel
Glenn Clingenpeel
Reputation 3,330
View All

Related Models For Sale

Used Ford F-150
2,174 Great Deals out of 195,110 listings starting at $290
Used Dodge Ram 1500
419 Great Deals out of 10,946 listings starting at $1,000
Used Toyota Tacoma
518 Great Deals out of 43,167 listings starting at $1,995
Used GMC Yukon
423 Great Deals out of 20,393 listings starting at $1,495
Used Chevrolet Tahoe
597 Great Deals out of 32,881 listings starting at $1,500
Used Chevrolet Camaro
350 Great Deals out of 31,370 listings starting at $2,500

Used Cars For Sale

2017 GMC Sierra 1500 For Sale
92 Great Deals out of 44,500 listings starting at $23,368
2016 GMC Sierra 1500 For Sale
89 Great Deals out of 3,512 listings starting at $17,670
2015 GMC Sierra 1500 For Sale
95 Great Deals out of 4,251 listings starting at $16,291
2014 GMC Sierra 1500 For Sale
92 Great Deals out of 4,195 listings starting at $13,995
2013 GMC Sierra 1500 For Sale
55 Great Deals out of 1,945 listings starting at $8,500

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.