When I started our team bus yesterday, (102D3), there was no fast idle. I thought well, something to look into and fix. Then the low air pressure buzzer wasn't on either. Then I noticed the head lights were on just sitting there idling... W.T.F.! They shouldn't come on till the Maxxi is turned off. (day light running lamps). The tack is wild. Then on the way to the game, the heat in the bus wouldn't quit, it got so hot I had to pull over and turn the valve off manually at the engine. Not long after, the engine starts cutting out... so I tell the team there is a problem and it's getting worse and we might not make it to the game. Once in Cranbrook, half way to our game in Creston, the boys are in a restaurant eating spaghetti, and I'm on the phone to Inland Kenworth, and Sun City Bus Lines, knowing I should not go any farther. I drive it to the shop. No running lights or brake lights by now. No interior lights either. The mechanic looks for 20 mn and can't find anything obvious. So we charter a bus from Sun City, transfer everybody and the bags by the restaurant, and I tell the driver to pick me up at Inland Kenworth where I will leave my bus for them to look at on Monday. Just as I drive into their yard, the engine quits and I coast to a stop! Not knowing a whole lot about electricity, I have no idea what could be causing such catastrophic and contagious failures. We'll see what the shop will find on Monday. I had 24 to 27 volts at the gauge the whole time.
We got to Creston at 10 to 7 for a 7 o'clock warm up and a 7;30 game, and won it in overtime!
I'll let you know what they find is the problem the next 2 or 3 days.
JC
Perhaps an idea past its time, but check the 12v tap from the batteries, if you have one. If there is a problem with the 12 v system, it will show up like you have described.
I have no ideal what system you have..On My 8y92 with dedec11 low voltage to the 12 volt control circuit caused a similar problem with the alt putting out 28 volts but the battery that supplied the 12 volt had a bad cell. just a observation.
Thanks for the comments guys, I will pass that on to the shop tomorrow am. I did look at the battery equalizer and the green light on it was on, showing that it is functioning properly. It is a 1995 with DD S60 with DDEC IV. The check engine idiot light never came on.
One funny thing: a couple days before, I took the 3 binder parts and service manual out of the bus and put it on a shelf in the shop, because it had been in the overhead comp. for years taking up space, and I had never used them on the road. Now I'll probably have to courier them to the mechanic so he can look at the electrical schematics. Ha, ha!
JC
Hi JC,
I had an issue with my Prevost 8V92 last week. I went to start it and it fired right up. I started walking to the house as it warmed up and it started to sputter and died within one minute. I tried to restart it and it would spin, but not fire. There was white smoke coming from the exhaust. I checked the codes in the DDEC and it showed almost every code on the chart, and some not on the chart.
My turn signals and hazard lights would glow but not flash, the water separator light glowed dim even though I had recently emptied it. I checked all the fuses I could find and they were good.
I put the battery charger on my 9 year old batteries for about three hours and just to make it easier to start I plugged in the block heater (it was in the 50's and usually starts when much colder). After it was warm and charged it started, but not easily. I let it run and it seemed okay. The next morning I went to the local International dealer and got 4 new batteries. While I was installing the new batteries I found some corrosion on one of the two ground connections. Now everything is working great.
Sounds like an issue similar to what robertglines1 had. Anyway, may or not be related to your problem.
Good luck,
John
Well...You Won The Game.!! Thats What Really Matters....CONGRATS :D
I Really Like That Last Post From JOHN (JOK) . Batterys And Grounds Can Do Some Really CRAZY Things To Your Systems. I Kinda Had Something Simular Happen Like That On My Diesel Dodge Truck..
I Would'nt Be Surprized If You Find Out Your Batterys/Ground Has Something To Do With The Freaky Problems Your Having.
I Look Forward To Your Post Tomorrow....Let The BET-ING Begin :o
10-4
JOHN 8)
Yea, the bad/weak 12 volt leg theory makes more and more sense as I have been mulling it over since you guys mentioned it. I now remember some of the relays in the front control panel were chatterring like Gramma's dentures on a cold day, as if they didn't have enough power to energize... I recently fixed the Vanner equalizer that hadn't been working right. It had a corroded blade terminal that was broken off and I soldered it back on. I think it is working right now, but the batteries were damaged, and I bet you if we replace the batteries, all will be good again. I'll mention all that to the mech. this morning.
Thanks again for the brainstorming,
JC
Grounds, grounds and more grounds.
Changing the batteries out disturbs the grounds, and may hide the culprit.
Check the big cables, both ends for their connection, and be VERY suspicious of internal corrosion in the cable ends. Any nicks in the jacket along their length too.
And then the same on the positive cabling.
On an in-service fleet, I've seen the battery cables corroded through with the green creeping death in under 6 years, hiding under the factory heat shrink at the cable ends...
happy coaching!
buswarrior
I spoke with the mechanic this morning. He replaced the batteries: they were showing 12.1 to 12.2 volts, even after charging them. He cleaned and replaced some battery cables that showed corrosion. He found a relay in the front control panel that doesn't close very well. It is getting good power: 12.3 v. When he jumps across it, everything works. It controls several other relays. MCI part # 7G-5-21. So I ordered it to be air delivered to them. Hopefully tomorrow, or Thursday at the latest, because I have to take the team to Fernie on Friday.
I'll let you know if it works.
JC
The guys at Inland-Kenworth in Cranbrook tell me they got the part from MCI and the bus is ready to go. Hard to believe that this one relay would cause all these problems... I'm getting a ride in the morning to pick it up. We'll see...
JC
Those batteries were shot. 12.6 is your goal.
Electronics is all about correct voltages down to 2 decimal places in many instances.
Bad relay contacts coupled with weak batteries, the rest of the sensing equipment is in the hole before you start.
Good to hear you are on the way.
happy coaching!
buswarrior
Well, I just picked up the bus and drove it home this morning. All is good and everything is working right.
The lesson learned for me here is this: you can get away with weak batteries and corroded ground terminals in an older vehicle with no electronics as long as it will start. But a computer controlled bus with electronics needs really good batts. fully charged, and clean cable connections everywhere. The old relay we had to replace might have failed as a result of not enough juice from the 12 volt leg. And a bunch of other relays just would not energize with only 12.1 volts.
Good experience for me. I promise to keep all electrical connections clean in the future... The new batts. should stay good for a while now that the equalizer is working properly.
Got to go now to pick up the team and take them to Fernie for a game.
JC
Matt seems like your prob