Hi Everyone. I have a 2001 Kenworth. The whole electrical system shuts down for a moment and then starts back up. Why? I have cleaned the ground wires, had the batteries checked, checked the alternator. Just can't seem to figure out what to do next. Any advice would be appreciated.
Sounds like you might have a intermittent short check all your battery cables from batterys to starter and from alt also check your main breaker and relay can't think where there at on kw right now does it #### everything off or does the engine die or start to and then come back on check ignition switch as well elect can be tricky just worked on a 06 357 Pete someone put motor mounts on the left side after that truck would just die when driving but start right back up got worse and worse turned out he pinched the alt power wire and it rubbed through the cover not enough to completely melt down but was sending power back through all the grounds don't know how he dident burn that one sown
I would check the main power wire from battery box to fuse box,there will be a big single wire plug between starter and valve cover right near top of ecm,will probably have a zip tie on each end
Yuo need to check the main cab power feed wire" p21AL" it will run from the main 135amp charge breaker in the battery box or the firewall to the PD box above the washer bottle.. it is a 2ga wire with a cpl bullet style connectors in it depending where the charge breaker is located. locate the wire and wiggle it at the connectors you will probably find the power will cut out to the cab.. by disconecting/cleaning and spreading the connectors you will most likely rectify the problem otherwise the issue may be the 135 breaker itself or a faulty connection inside the power distribution box which would have to be removed to be repaired... other than that i would need more info on the unit to properly t-shoot the issue
Thanks to all..I did replace the 135 breaker the other day which didn't fix the problem..so today I'm working on the wiring and connections as suggested. Again, thanks for your input and advice.
around the 2000 model year the new style power dist box's started to come out..if you have this style of box where the relays run horizontal intead of vertical look for the 70 amp relays ( there is 2 labled Acc bus and Ign bus ) try swapping them around or replacing them.. this can kill the unit as well however usually you would hear them click if they are tripping
I know this is a old post but in case someone else has the intermittent shut down problem I did exactly that on my 2006 Peterbilt 387 and swapped the relays around. I actually had to steal the one out of the sleeper because it got so bad it wouldn't even intermittently work to engage the starter since that is what the second relay up there was for.
