Peterbilt 387 no guages

Hey Chris you seem to know your way around these 387, you had any problems with the fuel gauge not registering right ?

 

No but sort of? Basically that can be as simple as a bad fuel tank gauge itself. Also known as a sending unit. Now if it works bit is let’s say very far off your tanks have a splitter valve or level valve to keep the tanks balanced. I fought one for awhile and just ended up running a few ball Valves from the feed line to the tank and just have it equal that way.

I do however have had issues with the plug from the sending unit on top of the drivers side tank. Meaning it got corrosion. So check that first. Start small in your process of elimination. Remember these trucks were “simple” but complicated with the way the wiring was done. So just be diligent and make sure your wires and plugs are good that are exposed.

sorry I don’t monitor the forums too often. But I will try to check back.

 

Hopefully this helps, its the diagnostic manual for the instrument panel in your truck. You have a module under your truck called an "interface module" that feeds your gauges all of their information including air pressures. Its on the inside of the frame rail back by the transmission so you'll want to check all your connections there as well.

https://www.ametekvis.com/-/media/ametekvis/download/technical-support/peterbilt_387.pdf?la=en

 

Likewise on the monitoring , thnx for getting back with me. On the gauges that blink red and go back and forth. Do you need to unplug connector from power board and clean it ?
Thank you

 

Blinking red lights and sweeping gauges means a power issue. 75 percent of the time I ran into this on a 387 I just took the ignition relay out (fuse box under the hood) and tightened up the female terminals for it. If that doesn't work just swap it with the starter relay right next to it. If all that fails there is troubleshooting steps for that exact issue in the manual I posted above.

 

I have only one gauge that does that and I have not actually jumped in on it. Truthfully if it’s an “extra” just unplug it. I know they provide good information but some of the 387s systems on these are not worth the effort. The Gauges are not peterbilt specifically. They are a 3rd party company and it takes a special scanner just for the gauges.

wrenchwrenchwrench is correct tho. Most of the time is a power issue.

 

Thanks Chris. If your a father. Happy fathers day

 

thank you very much. Be safe out there

 

My truck is 07

 

No problem I appreciate your expert advise