Ignition on, dash lights up, bus won't start......

[BrianE]

Jim,

A picture is worth..... The wires connect to the relay terminals with spade connectors. As Peter suggested, a short wire with male spade connectors could be used to jump the wires. Needless to say the wire gauge of the jumper would need to be at least as large as the leads they are jumping. This is not an exercise for the amateur (like me) besides, the relays are cheap.
______________
94Liberty XL

[JIM CHALOUPKA]

Thanks Brian, I see everything I need to know. I was imagining a more industrial type with round pins on the end that pluged into a socket. Similar to the old radio tubes.

I agree a handfull of what you have in a cigar box on the shelf is the easiest and best insurance. It never ceases to amaze me how much trouble and grief a little piece of foreign crap like that relay can cause.

JIM

[Petervs]

The relays are just plug in. These have individual wires with spade connectors attached that you push onto the relay. Some of the other relays plug into a receptacle.

I have no idea what the failure rate is. But if one out of the 4 fails, I think your engine will not run. So interchanging them would not solve a stuck on the side of the road problem.

The best thing is to carry one or two as spares, then if you suspect a problem you can substitute a relay to test your theory. Carrying a spare is much simpler and cheaper than calling a tow truck!

[JIM CHALOUPKA]

Petervs;The relays are just plug in. These have individual wires with spade connectors attached that you push onto the relay. Some of the other relays plug into a receptacle.

I have no idea what the failure rate is. But if one out of the 4 fails, I think your engine will not run. So interchanging them would not solve a stuck on the side of the road problem.

The best thing is to carry one or two as spares, then if you suspect a problem you can substitute a relay to test your theory. Carrying a spare is much simpler and cheaper than calling a tow truck!

Peter and Brian, after seeing the image and thinking about the situation, if all the important relays are similarly mounted I would for myself buy 4 new relays and mount them upside down on the same mounting screw on the panel board directly above the original.
Then in the shop under ideal controlled circumstances color code the relay terminals and the wires so that under what you could imagine to be the worst possible circumstances you could with nothing more than a flashlight move all the wires to the new relay very easily. JIM

[lewpopp]

Jim, no wheels for now,

Will you be hitch hiking to POG III? If so, will you work your way down to I-10? If so, tell us and we'll be on the lookout for you and blow the horn as we go by.

Naw, not really. We'd pick you up.

Lew

[Jon Wehrenberg]

Here is a little history of relays.

The pictured relay is typical on later model rivet coaches and maybe XLII coaches.

Early model rivet coaches used relays that looked like a small zinc plated can with threaded posts to attach the coil and current carrying wires. These relays could be found at NAPA strores and WW Grainger to just name two sources.

What is important for all bus owners to realize is the best thing they can do for themselves is to buy some spares and keep them in the bus. For the few dollars of investment you may save some really serious dollars for a service call.

But in the event of a relay failure, if you do not have a spare relay you can temporarily get going by placing a jumper between the two load terminals. The time to get an understanding of this is when you have a coach sitting in your garage and you can play around with a tester and some wiring diagrams that you can download from the Prevost site, not when you are in a remote area of some national park.

Also, if you cannot get the coach to turn over using the key, see if you can start it from the rear. If you do that you will not have any gauges but you can get it running.

[lewpopp]

If I'm on the right page on this, a good description of that switch is a lot like (not exactly) a solonoid on an old Ford.

Lew

[Jon Wehrenberg]

That's the one Lew...

I forgot to mention in the earlier post that the Bosch relays are a vast improvement over the older large relays. On our 1987 vintage coach the drivers AC fan, the lights, the start circuit, the battery isolator, and a few other things had those can type relays (I called them solenoids) and I was always replacing them because there were so many and because they just seemed prone to failure.

[rfoster]

Well I got lucky tonight, no not that way men! I was getting the bus out ready to make a two- three day run leaving out Tues, and the bus fired up and ran for a short time, spit and sputtered a number of times and then died -couldn't figure out what was going on. I had my three year old grandson in the copilot seat, but when I fired it up and to let the air build I looked to the left out of the rear view mirror, I am talking for just a second. Turns out that my co pilot had slid over to the buttons and had flipped the alarm button to the point it disabled the engine. To say the least - I didn't know it would disable the engine, and two I didn't know the button had been flipped. So I crank it for a resonable amount of time. Get the Granny to take the kid while I try to diagnose the problem and after a while of me at the back and the front, in and out, thinking about calling A1, getting pretty torqued, I look down and start examing switches on the dash, questioning in my mind the position of all of em. Turns out the alarm switch was down and should either be in the middle or up. All is well at this time. Point is a three year old great little boy can move really fast when you ain't looking. 2 hours shot.

[merle&louise]

Roger,

I can identify with that problem. My grandson (3 years old also) was playing around in the bedroom of my '93 and he hit the ALARM button. My son-in-law is driving along and all of a sudden the horn starts blowing. On and off non stop! My son-in-law tried everything he could think of but couldn't stop the horn from blowing.

He calls me on the cell phone and asked me where the fuse was for the horn, I ask why, and he tells me the horn is blowing on & off non stop. I immediately knew what had happened and told him to walk to the bedroom and turn "off" the ALARM button next to the bed.

Problem solved: grandkids, you gotta love 'em