question on 4l80E input speed sensor

[bezerk]

well, i had the 4l80E rebuilded by a company, and after the rebuild it went in safety mode.
found out with a scanner that computer thought it had too much slip.

output was like 750rpm and input 400rpm. (undefinied gear ratio)
can it be that there are 2 input speed sensors, and you can exchange the connectors that this will happen?

thanks

 

[George Blake]

Re: question on 4l80E input speed sensor

Make sure the sensors are hooked up right. You will get a ratio error if you mix the tiss and toss sensors up.
On OEM 4L80E apps 99% of the time, something is wrong externally causing the problem. TPS, 12 volt feed, ground, something with the TCM, ect, causes the problem. I replace the external sensors on every build I do. If you need new external sensors, LMK.
Check all connections first since the trans was pulled and reinstalled.

 

[bezerk]

Re: question on 4l80E input speed sensor

yeah.i didn't take any sensors out, i just plugged every connector back in, and looked inside the connector to see if it has been used.
i am just wondering if i hooked up a sensor bad ( 2 of the same connectors but different readings), or they exchanged sensors inside the transmission.

this truck is going away, new engine @150k miles and new tranny at 170k miles, i have been patienly waiting for the workshop to solve this problem (10 weeks), to pick up the new duramax we bought.

thanks man