Bus shuts off when driving

Onlyfordguy · 05-26-2019, 01:08 PM

My 2001 international RE 7.3 just left me on the side of the road. It was driving fine, all gauges read good, then shut off and just coasted to the side of the road. It would not even crank over, just clicked when I tried to restart. Batteries are good. When I opened the electrical panel I had power coming from the battery to what I call a solenoid then no power coming out to supply the fuse panel. I grabbed a jumper wire and bypassed the solenoid but still couldn’t power the fuses. It was so strange. On the picture I circled the solenoid and where it supplies the fuse box. The solenoid and the similar one underneath it were very hot. I appreciate any advice.

EastCoastCB · 05-26-2019, 01:19 PM

That solenoid is easy to get. they go bad due to the environment they're in. The doors don't seal well allowing lots of moisture in.
I've had to replace one.

Johnny Mullet · 05-26-2019, 02:01 PM

I also suspect one of those solenoids.

superbusWI · 05-26-2019, 02:19 PM

had that exact thing happen with my t444 vista half way through montana once - I had recently replaced the starter. my terminology in the following will most likely not be accurate, but the fix worked nonetheless

the computer that controls fuel supply (and too much other stuff) picks up its power from the hot post of the starter, along with like 7 or 8 other things on the same post. often the ring on the end of the cable gets corroded or the nut on the post loosens enough to disallow a good connection, killing the bus.

i'd go down to starter - disconnect batt's 1st obv - pull the nut off the hot post (it's a 3/4 on mine, long socket extention worked well but i'm FE) and examine everything that draws power form there for corrosion or wear. put everything back on real nice too, I've had things wobble loose on there more than once, and solved it with a 1/4 turn of the hot post's nut.

better to check the free stuff 1st in any case - best of luck and keep us updated

EastCoastCB · 05-26-2019, 02:23 PM

One is for the starting system and the other is for everything else- At least on the buses I've had. They're both the same part numbers.
Its easy to test em with a multimeter.

superbusWI · 05-26-2019, 02:26 PM

yeah it looked like pretty much everything on a stock setup draws its power off that post, I've seriously contemplated splicing some of the stuff together into 2 or 3 larger rings instead of so many small ones... maybe another day lol

that could explain why he couldn't jump the fuses past the questionable solenoid - maybe that particular solenoid is one of those relay gates (again, probably wrong terminology) this power system uses?

cadillackid · 05-26-2019, 03:36 PM

does the WARN light come on for 2 or 3 secxonds when you turn the key on?

if not then the computer isnt booting up and wont allow the starter to even crank..

im not familiar enough with the RE nodel to know if theres a separate chassis fuse panel or not... some of them do whiuch is where the ECM bat and ECM IGNITION fuses would be.. these are usually not dependent on those solenoids to power the engine..

also make sure something didnt come loose in the rear control box for the engine.. ie the rear kill switch wire came off or such..

Native · 05-27-2019, 02:31 AM

Quote:

Originally Posted by superbusWI

yeah it looked like pretty much everything on a stock setup draws its power off that post

... except for the Radio Shack device just below the solenoid!

Onlyfordguy · 05-27-2019, 09:34 PM

Thank you all for the help, we had to tent camp for the weekend and the cops towed it before I could get back to it. 800 bucks later it’s back in my driveway. Not sure when I’ll be able to try your suggestions but I’m hoping for soon. I will keep you posted. Also, one suggestion said they are easy to test with meter. Could someone walk me through how? Thanks guys.

o1marc · 05-27-2019, 10:17 PM

Quote:

Originally Posted by Native

... except for the Radio Shack device just below the solenoid!

20amp heavy duty noise filter.

CMORGANSKOOL · 05-27-2019, 11:03 PM

Quote:

Originally Posted by o1marc

20amp heavy duty noise filter.

I need one of those. My cab goes crazy when I turn on the heater fan.

o1marc · 05-27-2019, 11:32 PM

Quote:

Originally Posted by CMORGANSKOOL

I need one of those. My cab goes crazy when I turn on the heater fan.

https://www.ebay.com/itm/RadioShack-...AAAOSw0QBb50cr

CMORGANSKOOL · 05-28-2019, 09:24 AM

Quote:

Originally Posted by o1marc

https://www.ebay.com/itm/RadioShack-...AAAOSw0QBb50cr

Thanks, and I wonder if this is the reason for my intermittent stall and occasional rough run at start? I just assumed it was related to the fuel filter since it started after I changed it.

Onlyfordguy · 05-30-2019, 08:03 PM

So I’m still trouble shooting. After reading these posts I went to check and none of my engine warning lights come on when I turn the key with the exception of the red brake light. The compressors don’t even start to fill up the air brakes. Nothing! After running through it with a multimeter I have power to the fuse panel until I try to crank it, the the top solenoid clicks and kills the power. It’s acting exactly like it did when the starter interlocks on the emergency doors wouldn’t allow it to start. I’m wondering if it could be that? I disconnected them and bypassed them at the solenoid, it started so I assumed it was fixed. Clearly not. If you have time I did make a YouTube video to send to a family friend who is a diesel mechanic. Here is the link https://youtu.be/vwpwJ9bMcT8 thanks guys/gals for all your help!

cadillackid · 05-30-2019, 08:39 PM

if the WARN light isnt coming on when you turn the key to IGN on then one or both of the 2 computer circuits arent getting power.. well ultimately the computer isnt booting up.. these computers are pretty hearty they dont die very often so I suspect a power issue to it...

one circuit is a BAT circuit (hot all the time key on or off) and the other is an ECM IGN circuit..

are there any lines on that door diagram that pertain to the engine or chassis? (ECM,Trans, Turn,Headlights) or is it all body equipment?

some of these busses have a separate small fuse panel that handles core chassis equipment like engine control and headlights, etc..

-Chris

Brad_SwiftFur · 05-30-2019, 10:28 PM

I've driven a few trucks that had a feed right off the batteries powering stuff (ECM? Something else?) and the connection worked its way loose or got corroded. Cleaning and tightening the connection restored whatever the function was supposed to be. Sometimes it really is just the simple stuff.

skidfrog · 06-10-2019, 09:39 PM

my comment is probably irrelevant but maybe relevant for much older buses ?......I remember the exact thing happened to me in a car I was driving ages ago......pure mystery to me at the time but it turned out to be a hairline crack in the distributor cap .

My ignorance on the topic is immense....so I bought a new ish GMC 6 litre gas

Onlyfordguy · 07-11-2019, 10:53 AM

Thanks for all the support and advice. I ended up giving in and having it towed to an International dealership 30 miles away. Turned out to be a break in the supply wire to the ECM combined with a malfunctioning component on the starter that protects it from overcranking, didn’t know that was even a thing. All fixed now though. However non of my turn signals work now and don’t even flash on the dash.....always something. Anyways thanks again guys/girls.

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