99 Yukon transmission and gauges done..

[steves99YukonSLT]

Hi I'm new here but I have an issue with my truck so here goes, as I was pulling out into traffic, I turned right onto the street and I hear this clank , not like the sound u- joints make when there bad but like a slipping sound , I get back to my work as I'm pulling into the parking lot the trans starts whining and I lose my dash lights along with the gauges, park it and put it in reverse more whining and no reverse, at this point I know that I need a new trans. my question to all of you,what would have made lights and gauges stop working? even my gear indicator is gone if any body could help me b4 I dump a bunch of money in it would be appreciated. thanks, Steve

 

[SunlitComet]

exactly which gauges and lights did and did not work? it makes a differences in diagnosis.

 

[steves99YukonSLT]

ok well I went out and fired it up so I have dash lights, the speedo and the tach do not work though, I guess I should have done that b4 I posted sorry, I haven't driven it since march. and the gear indicator also not working

 

[SunlitComet]

on fuse block to the left side of dash when door is open. fuse 20 called trans. it powers exactly those things and provides the + power supply to the shift solenoids. if that circuit lost power and your tranny was already weak then the power loss my have strained it. if the use is blown replace it and see what happens.

 

[steves99YukonSLT]

Tcase or 4wd? There is no fuse in the 4wd, and T case is not blown.

 

[SunlitComet]

fuse 20 prndl. not 24. btw i you have 4wd you should have a 20 amp fuse in both tcase and 4wd in order for the system to work.

 

[steves99YukonSLT]

fuse 20 prndl. not 24. btw i you have 4wd you should have a 20 amp fuse in both tcase and 4wd in order for the system to work.[/QUO

thank you I appreciate your help and I never used the 4x4 so good to know b4 I do , thanks again , the prndl fuse was not blown either , would it be in the trans then?

 

[SunlitComet]

if still no functions from those items probe for voltage at that fuse with the key on if there is no voltage present on the fuse then there is possibility that the ignition switch is faulty. it is important to fix those gauge indicators problems first since those circuit also powers the tranny solenoids. you understand the reasons why i m sure. use the diagrams below as aids.

 

[SunlitComet]

when you get power back on that circuit those gauges will work s well s gear indicator and the tranny gets power. clear any accumulated p-codes that likely did not set off the cel and reevaluate the tranny failure for accuracy.

 

[steves99YukonSLT]

We got power back to the PRNDL fuse, was a relay , tach works now but speedometer wont work , we replaced both speed sensors on the trans case , and the neutral safety switch on the side of trans, will start , if you put it in drive will not shift out of first , but will if I manually shift from 1st to 2nd but will act like its in neutral when I shift into third manually. does it need recalibrated?