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CISDbusman
Advanced Member

293 Posts

Posted - 12/06/2019 :  08:51:30 AM  Show Profile  Reply with Quote
The in-laws and myself have to take a road trip over Christmas to Florida for my nephews wedding.... My BIL's motorhome was going to be the means of getting us all down there.... Motorhome no starty last weekend.

It drove to where it is now. I am figuring wiring issue or electrical side of high pressure oil system. I am betting the IPR is stuck!?

Anyone have a checklist for a 3126 no-start? I have no laptop so we are chasing the basics.

Thanks all!!!

Bluenozer
Advanced Member

Canada
354 Posts

Posted - 12/06/2019 :  09:26:50 AM  Show Profile  Reply with Quote
1. when yo turn on key do both amber and red check engine lights come on and go back out if not- check your power and grounds
2. by your story it is turning over , if it is does it have base oil presssure?
3. fuel filters full,if not fill and try to restart, does it have a primer- if so does it work? does it leak?
4. and by story no CEL staying on
5. what does ether do for it?
6. full field the IPR with 12 volts and try to start- What happens?

OEM trained in wiring and all engine platforms for 20 years
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tigger2
Advanced Member

USA
444 Posts

Posted - 12/09/2019 :  05:17:57 AM  Show Profile  Click to see tigger2's MSN Messenger address  Reply with Quote
Is this an electronic engine, or a manual fueled engine? Check for presence of grid heater and unplug relay connector b before putting ether to it.
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CISDbusman
Advanced Member

293 Posts

Posted - 12/09/2019 :  06:16:54 AM  Show Profile  Reply with Quote
quote:
Originally posted by Bluenozer

1. when yo turn on key do both amber and red check engine lights come on and go back out if not- check your power and grounds
2. by your story it is turning over , if it is does it have base oil presssure?
3. fuel filters full,if not fill and try to restart, does it have a primer- if so does it work? does it leak?
4. and by story no CEL staying on
5. what does ether do for it?
6. full field the IPR with 12 volts and try to start- What happens?




Thanks for the reply!! I think you nailed it with the your first suggestion. When I got over there Saturday am he had it running already (ugh!!). Said he wiggled "some" of the wiring in the engine bay (under the bed as its a pusher) and the intake heater and CEL lights came on on the dash and it started. We drove it 60+ miles Saturday night with no issue. Got up the next morning and it wouldn't start. He said the intake heater and CEL were not lit up on the dash either. He is going to go over the wiring in the engine bay and see if he can locate the issue.

I am gonna dig around and see if I can locate a wiring schematic for it to aid in finding the issue.

Electrical issues separate the techs from the nut twisters!!

Thanks again for the info!!
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CISDbusman
Advanced Member

293 Posts

Posted - 01/02/2020 :  12:38:34 PM  Show Profile  Reply with Quote
Update. We are home after 2200 miles of travel. Motor home did well till it didn't.....

On our way home from Pensacola we stopped for the night in Biloxi at an Elks Lodge that had RV hookups. After opening and closing all the underneath storage for various items my BIL noticed the battery tray had lost the pin that kept it from sliding in and out and had pushed it back in with his foot. We would secure it in the am.

We get it all leveled up and set up short of the shore power only to find out his 30 to 50 amp adapter plug was to big to fit in the weather proof box on the pedestal. Grrr!! So we decide to move to the Casino RV park only to find the Motor home was back to its old ways. Spinning over but not starting.....

So no CEL or Intake heater lights on the dash again.

After an hour of tinkering with it my BIL and SIL were ready to burn it. tensions were high so I crawl under it and started thinking as to what had changed since our last stop. I knew I was chasing either a bad ground or positive issue!!

We had to raise the home up fairly high to get it level so I started digging around in the rear where the hydro cylinders mounted thinking maybe the lift structure was moving an engine or body ground or something but found nothing suspect.

So now I moved to the positive side of the home. These things are SUPER BUSY with wiring and different systems. Generator, house batts, invertor-chargers, solar, oh my!!

Furthest rear storage area on passenger side houses all the engine stuffs, dipsticks, fuel filter and means of monitoring and starting/stopping engine. I thought maybe the kill button had failed or wiring to it was iffy so I started tracing wires and such in this area.

Through my digging I noticed a screen door spring around the battery cables just behind and between the frame of the start and house batteries. Area had had some shoddy work done at one time as there was lots of electrical tape and white zip ties holding various things together in bunches.

By now it was dark, cold and the lower half of my body was getting wet do to it sticking out from under the coach with the fog rolling in. With flashlight in my mouth I finally uncover three single GM style fuse holders with one lead from each attached to the start batts...... Two were missing the covers and looked bad so I scraped around on the terminals and the fuses. After each cleaning we tried starting it and still no dice or dash lights. The third one (its always the last one) had a cover but upon removing the fuse I seen that it had been warm at some point and had melted the fuse body and the terminal was discolored. I cleaned it up and put just a little twist in the blades of the new fuse and told my SIL it will start now. I heard the key click on and she screamed THE LIGHTS ARE BACK ON and it started.

Best I can tell from my process of elimination as to what had changed is that when MY BIL slid the battery tray back in the 1" or so it wiggled the already unhappy fuse/holder causing it to loose connection.

After talking with my BIL during the move to the new site he said that he had had the batteries slid out before our trip checking cables and house batteries condition and while it was out with charger on it the engine wouldn't start..... He started messing with wiring in the engine bay (under the rear bed), then slid the battery tray in for the night and the next morning it was like there was never an issue as the engine started.

I had saved to my phone the pinout for the ECM encase it acted up so I could just hot wire it if needed.

The trip and my in-laws marriage was saved!! We had an amazing trip, seen some wonderful sites and ate some awesome food. I have a new respect for cajun seafood now also!!!

Thanks to all for your help above!!

Now to find a supplier for the OEM GM fuse holders so I can replace them and secure them up and away from the batteries.

Its always the little thing!!

My wife found the bad fuse in the laundry
https://www.snapfish.com/library/share?via=link&token=55CbvzeKK-4Odrr1uHJ56Q/AUS/27951133028070/SNAPFISH

Edited by - CISDbusman on 01/03/2020 12:31:00 PM
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aaronwilmoth80911
Top Member

536 Posts

Posted - 01/03/2020 :  05:23:34 AM  Show Profile  Visit aaronwilmoth80911's Homepage  Reply with Quote
Thanks for updating with thorough information. Glad you got it figured out.
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buster133
Top Member

USA
506 Posts

Posted - 01/03/2020 :  11:51:58 AM  Show Profile  Reply with Quote
Check out this link for the fuse holders. If I'm thinking correctly, what you might need is half way down the page

https://www.bmotorsports.com/shop/index.php/cPath/150?osCsid=8aln4q5qcs0qfirttfuq78eav3

[URL=http://s7.photobucket.com/user/buster133/media/6f2e0703-1970-4ac9-bb1f-b6b9d7c12297_zps1741e113.jpg.html][/URL]
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CISDbusman
Advanced Member

293 Posts

Posted - 01/03/2020 :  12:33:59 PM  Show Profile  Reply with Quote
quote:
Originally posted by buster133

Check out this link for the fuse holders. If I'm thinking correctly, what you might need is half way down the page

https://www.bmotorsports.com/shop/index.php/cPath/150?osCsid=8aln4q5qcs0qfirttfuq78eav3



Yes Sir. Thank ya much!!
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