For the trucks we've had to deal with, the battery is actually part of a chip on the board. It's a Dallas DS12887. Sometimes, it's under an aluminum enclosure (have to carefully cut off) It's usually the biggest thing on the board. You have to be good with a Dremel and a soldering iron if you wanna tackle this job.

Here's a video explaining how to repair the chip. Note that you will have to remotely mount the battery holder somewhere other than suggested because there's not room above the chip with the housing assembled.

https://youtu.be/NdlSfqto_0o?si=WV6f_aKNlFUqNVDJ

One more note, you can buy new chips on their own, but they've not been manufactured in years, so you are counting on a battery that is several years old.

I dont have any display available right now but its like example cr2330. You should see it after you open the display. (Displays circuit board)

Thank you for the reply.
Do you know where it is located inside the dash?
I opened it, didn't find any battery.
If you have some pictures or information of it, please send it if you can.

There is a little battery inside the dash. Replace the battery, it will solve the problem.

I have the same problem, did you solve the problem?

battery in dash are dead.... try to replace it , it is a lithium cell i mean

Hi Justus,
thanks for reply, that was one of the first things i looked at, all wiring is good.
i have since been told that there is a battery in the display which holds information, i have yet to strip & have a look

hour meter info comes from logic card so check wiring first between logic-display. problem cause is possible in logic card too.