Coach Will Not Start

[Trige Gleim]

I think I have found a problem and I sure hope it's the only problem.  Inside the distribution box there are 6 large fuses, 4 on the right and 2 on the left of the relay.  They all look good except one.  Do you think this is the culprit?  If so, here are a few questions. 1) Where do you buy them? 2) Should I buy an extra to keep on hand? 3) What precautions do I take removing and installing a replacement?  Please let me know.  Thanks

[Steve Huber]

Trige,
The 2 fuses in question feed the alternator and the printed circuit board in the front electrical bay. As I suggested earlier, check to see if you have 12v on the lug on the PCB. If not the fuse is bad (or check for 12v on both sides of the fuse).
See attached diagram. These diagrams are accessible by going to Private Members  Only board and selecting the Coach Link post.
But, I don't think this is your problem as a lack of 12v to the PCB would have prevented the dash lights from doing their thing. Check F4 if you haven't already done so.
Steve

[Trige Gleim]

Trige,
The 2 fuses in question feed the alternator and the printed circuit board in the front electrical bay. As I suggested earlier, check to see if you have 12v on the lug on the PCB. If not the fuse is bad (or check for 12v on both sides of the fuse).
See attached diagram. These diagrams are accessible by going to Private Members  Only board and selecting the Coach Link post.
But, I don't think this is your problem as a lack of 12v to the PCB would have prevented the dash lights from doing their thing. Check F4 if you haven't already done so.
Steve

I did check the F4 fuse visually and it is good.  I do not know how to check to see if I have 12v on the lug on the PCB or how to check for 12v on both sides of the fuse.  Do I use a multimeter for this?  If so, what setting for the multimeter and how do I connect it?  I warned you ha.  Thanks for the diagram!

[Steve Huber]

Trige,
You can use a multi-meter or a 12v probe. A multi-meter is best but a probe works also. Harbor Freight sells a meter for less that $10 that will work fine. https://www.harborfreight.com/7-function-digital-multimeter-90899.html  Plug the red cord into V - ma  and the black into com on the meter. Select DCV and 20. Put the black probe on the ground lug on the Printed Circuit Board (lower right as you look at it) and the red probe on the chassis  lug (lower of the 2 lugs on the center right of the PCB). You should see 12-14 volts displayed. If not move the red probe to the upper  (house) lug. you should see 12-14 v displayed. If you don't see 12v here there is a problem with the way the meter is set up.
Assuming you have 12v in both places, check the fuse. You can't tell if it is bad by looking at it unless you pull it and see that the link is blown. Either simply replace it or, using the meter, check for 12V on both sides of it by touching the red  probe to the exposed metal tabs on both sides of the top of the fuse.

Another option is to use a voltage probe. https://www.amazon.com/Voltage-Continuity-Current-Tester-Indicator/dp/B01BGZ9XRS/ref=sr_1_5?ie=UTF8&qid=1517271312&sr=8-5&keywords=voltage+probe
They are available at most auto parts and home improvement stores. Simple hook the clip to ground and touch the probe to where 12v should be. The indicator will illuminate if 12v is present.
Steve

[Trige Gleim]

Trige,
You can use a multi-meter or a 12v probe. A multi-meter is best but a probe works also. Harbor Freight sells a meter for less that $10 that will work fine. https://www.harborfreight.com/7-function-digital-multimeter-90899.html  Plug the red cord into V - ma  and the black into com on the meter. Select DCV and 20. Put the black probe on the ground lug on the Printed Circuit Board (lower right as you look at it) and the red probe on the chassis  lug (lower of the 2 lugs on the center right of the PCB). You should see 12-14 volts displayed. If not move the red probe to the upper  (house) lug. you should see 12-14 v displayed. If you don't see 12v here there is a problem with the way the meter is set up.
Assuming you have 12v in both places, check the fuse. You can't tell if it is bad by looking at it unless you pull it and see that the link is blown. Either simply replace it or, using the meter, check for 12V on both sides of it by touching the red  probe to the exposed metal tabs on both sides of the top of the fuse.

Another option is to use a voltage probe. https://www.amazon.com/Voltage-Continuity-Current-Tester-Indicator/dp/B01BGZ9XRS/ref=sr_1_5?ie=UTF8&qid=1517271312&sr=8-5&keywords=voltage+probe
They are available at most auto parts and home improvement stores. Simple hook the clip to ground and touch the probe to where 12v should be. The indicator will illuminate if 12v is present.
Steve

I checked the voltage on both the chassis lug and house lug and they read around 12.5v.  I also confirmed again the F4 fuse to be good by both pulling the fuse and seeing that the link is unbroken and also doing a continuity test on it with the multimeter.  Additionally I replaced the ANL 200 fuse in the distribution box that was blown.  Still no luck getting the transmission control pad or the valid system control pad (air bags) lights to come on and of course it still wouldn't start when I tried.  I have not pulled the side panel off to look at the module under the transmission pad yet.  I understand there's a battery and ignition fuse there.  Thoughts on next step?

[Steve Huber]

Trige,
If the 200A fuse was blown, there must have been an arc when batteries were installed. So, you may have other problems as other fuses could have been blown. I'd check for fuses inside the console, both for the transmission panel and the Valid/Power gear system.
Steve

[David T. Richelderfer]

Without a lighted N (neutral) on the transmission keypad, your engine will not start.  The transmission must be alive and report an N (neutral) shift status to the engine.  Yes, under the transmission keypad there is a black clam-shell box about 6"x8"x1" full of electronics along with an auto fuse or two.  Check the fuse/s.

[Trige Gleim]

Without a lighted N (neutral) on the transmission keypad, your engine will not start.  The transmission must be alive and report an N (neutral) shift status to the engine.  Yes, under the transmission keypad there is a black clam-shell box about 6"x8"x1" full of electronics along with an auto fuse or two.  Check the fuse/s.

I did have a spark when I re-installed the batteries. I can't find the VIM.  I removed both side panels under the keypad and its not there.  Its not in the electrical bay either.  Someone said it may be in the dash but I haven't looked.  I also heard it may not have one and gone to multiplex wiring instead?? I sure would like to know where this thing is or if my coach even has one.  I'm heading back over the coach around 10am EST to check for more potential blown fuses in the electrical bay and the distribution box.

[Trige Gleim]

Trige,
If the 200A fuse was blown, there must have been an arc when batteries were installed. So, you may have other problems as other fuses could have been blown. I'd check for fuses inside the console, both for the transmission panel and the Valid/Power gear system.
Steve

Based on the tests you've had me do, are you convinced its not a battery or ground issue?  I don't know enough to answer that.

[Keith Phillips]

I am not sure if this can happen with the newer coaches but I shut my Marquis off in gear. When I went to restart it, just a click. I had to crawl under the coach and put the transmission in neutral and it started. I don't think I'm supposed to be able to shut it off in gear, but it would not restart until moved the air actuated lever on the side of the transmission into the neutral position.

[Trige Gleim]

I am not sure if this can happen with the newer coaches but I shut my Marquis off in gear. When I went to restart it, just a click. I had to crawl under the coach and put the transmission in neutral and it started. I don't think I'm supposed to be able to shut it off in gear, but it would not restart until moved the air actuated lever on the side of the transmission into the neutral position.

I had it started where its sitting a few weeks ago.  Then I started having the battery problems so I took the batteries out to have them charged and put them back in, the coach has never moved during the whole process so my situation is different.  Thanks Keith.

[Steve Huber]

Trige,
If you read between 12 and 14V on your meter when measuring chassis voltage at the electrical bay PCB (under dvrs positions) your power and ground are probably OK.
Steve

[Trige Gleim]

Well, I heard the most beautiful diesel engine ever running a short time ago.  Yes, the mystery has been solved.  After replacing about a half dozen cooked fuses I found the culprit in the rear distribution box.  It was a 15a fuse called VEC-2 Batt Transmission on the bottom left of the panel.  Once I replaced the fuse, a TCM light on the panel lit up and a short walk to the drivers seat revealed the transmission control pad was lit!  So the final results are...I replaced blown electrical bay fuses F10, F43, F45, F46, and F81.  F46 got the Valid system to fire back up, and F43/F45 eliminated the fault code I was getting on it.  In the rear distribution box I replaced the far left ANL 200a fuse and the VEC-2 fuse.  This coach does not have the VIM (Allison Transmission Box) that we were searching for.

I'd like to thank you all on the forum for the interest and comments with my situation.  You have taught me a lot.  Also thanks to Beaver Coach Sales for their support.  It's comforting to have a community of great folks!

[LaMonte Monnell]

Happy you got it finally. It is nice when they start right up.....

[Pat Long]

For anybody on this thread, What could have Caused All The Fuses TO Blow?