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Skip426 · 02-08-2013, 12:46 PM

I'm bringing this back as a new thread even though others have posted to the issue, under various other headings. eg., Hard start , no- start, rough run and engine quit. 97 through 01 , Cat 3126 & 3126B that I'm sure of and this may apply to other years as well.
The battery power to the Cat, Engine Control Module, is supplied through an in-line fuse ; between the battery and the ECM; the fuse and holder are subject to failure due to age & corrosion, and can leave you stranded.
I have found the fuse in my wiring schematic ( 20 amp in-line ) but have yet to track down it's exact location in the coach.
A fellow RVr here in the park had his engine cut out during warm up , before he moved from his site. He had an idea that the problem was no battery power to the ECM, but without a pin out of the connector, we could not confirm, and looking over the harness , we could not locate the fuse, even with info from others here in the forums.
Coach was towed to a Cat dealer. and repaired.
100 miles towed, 2hrs search by a Cat mechanic, to locate the bad fuse holder and replace same, total 3 days travel time lost due to a HIDDEN fuse.
I'm now on a misson to find the fuse on my coach, because Murhpy says
he's coming for me. When found this will be location #9 for 12 volt fuses in this coach.

wb7auk · 02-08-2013, 12:58 PM

I found mine in the battery compartment, it was a red wire the went from the positive
terminal of the house battery's to a inline fuse then to the ECM.
Have no idea if this was someone's fix or it came that way from the factory.

Skip426 · 02-08-2013, 02:35 PM

Thanks Art, I found a fuse next to a power post under my battery tray, looks like an add on so the previous owner may have had work done, wiring is taged with duct tape, with B-12 circuit in ink marker, not the #s from my diagrams, haven't got under the bed yet to see if the wiring is in fact hooked to the ECM. Wiring diagrams show a 4 wire connector 150mm from the ECM plug, and I won't know if I've got the right fuse till I find that connector, or track the wire I found to the ECM.
I would pull the fuse and attempt to start, but I'm level on the jacks right now and don't want to run and air up if it's not the one.
Tomorrow

wb7auk · 02-08-2013, 04:19 PM

Quote:

Originally Posted by Skip426

Thanks Art, I found a fuse next to a power post under my battery tray, looks like an add on so the previous owner may have had work done, wiring is taged with duct tape, with B-12 circuit in ink marker, not the #s from my diagrams, haven't got under the bed yet to see if the wiring is in fact hooked to the ECM. Wiring diagrams show a 4 wire connector 150mm from the ECM plug, and I won't know if I've got the right fuse till I find that connector, or track the wire I found to the ECM.
I would pull the fuse and attempt to start, but I'm level on the jacks right now and don't want to run and air up if it's not the one.
Tomorrow

Well I found mine just because I saw this wire and fuse and was already
doing some personal work on that area and traced it out as it seemed
odd to me.

LDP243 · 02-18-2013, 11:19 AM

I found a 20 amp inline fuse coming from my house batteries labeled Allison transmission. Is this what you all are talking about? according to my manual I should have another one coming from the batteries that go to the Cat starter,but I have not found that one as yet.

wb7auk · 02-18-2013, 11:42 AM

Don't you just love it when things are changed and no paper work.
So far my TW is working so as they say if it is not broken do not fix it.
Of course unless there is a hazard.

TQ60 · 02-18-2013, 02:25 PM

The fuse was installed by the chassis manufacturer or the body builder.

It. Would seem like an email to both with the VIN would be in order.

Should be a simple question and answer.

wb7auk · 02-18-2013, 03:11 PM

Quote:

Originally Posted by TQ60

The fuse was installed by the chassis manufacturer or the body builder.

It. Would seem like an email to both with the VIN would be in order.

Should be a simple question and answer.

National has been out of business for several years.

mel s · 04-25-2013, 12:58 PM

Quote:

Originally Posted by LDP243

I found a 20 amp inline fuse coming from my house batteries labeled Allison transmission. Is this what you all are talking about? according to my manual I should have another one coming from the batteries that go to the Cat starter,but I have not found that one as yet.

My coach has some inline fuse holders near the batteries, in the wires connected to the positive posts of the batteries.
Those wires power various things, (among them the Cat ECM and the Allison VIM).
Believe it or not, I payed $1500, (it was $2400 before I refused to pay that much), for a "authorized Allison shop" to diagnose and replace a "bad wire" from the positive post of my chassis battery to the Allison VIM, (Vehicle Interface Module)...
20 feet of 14ga wire, 2 connectors and LABOR.
Mel
'96 Sahara