M2 repeatedly burning F19 fuse

Noah Mausser 9 posts since Jan 13, 2017
M2 repeatedly burning F19 fuse Sep 25, 2019 5:29 PM
ANYONE HAVE ANY ISSUES WITH F19 FUSE REPEATEDLY BURNING OUT ON M2 CHASSIS?
CUSTOMER HAS BEEN HERE REPEATEDLY WITH NO RIGHT HEADLIGHT, NO TURN SIGNALS, AND NO
TAIL LIGHTS COMPLAINT. EACH TIME THE F19 FUSE HAS BEEN BURNT OUT. WE HAVE NOT BEEN
ABLE TO REPEAT THE FAILURE IN THE SHOP. HE WILL TAKE, AND WITHIN A DAY OR 2 IT WILL BE
BACK WITH SAME ISSUE.

Jon Pedley 52 posts since Nov 13, 2014
Re: M2 repeatedly burning F19 fuse Sep 25, 2019 5:56 PM
Has anything been added??? Have you put an amp meter on this to see what kind of amps this is drawing??
If its right at the threshold it may not blow right away, but after a spike like turning on the lights, might put it over
at times. I'm curious what it is drawing while working?

Kyle Siebert 4,084 posts since Nov 14, 2014
Re: M2 repeatedly burning F19 fuse Sep 25, 2019 6:15 PM
Re: M2 lost of power in dash and engine dies when hitting a bump
i put that post because it explains the process of adding inline fuses. You can always install them to all the
outputs that vbat supplies power to. Release it to the customer. Then have it rechecked after two weeks.
Check all the inline fuses and the blown one will be the circuit with the issue. It will blow the inline fuse before
the vbat f19. If it does blow f19 again, then your looking at the circuit from the PDM to the BHM or chm.

Paul Mathers 112 posts since Feb 14, 2018
Re: M2 repeatedly burning F19 fuse Sep 26, 2019 3:21 PM
This is such an excellent idea! The electrical nerd in me is drooling over this lol

Kyle Siebert 4,084 posts since Nov 14, 2014
Re: M2 repeatedly burning F19 fuse Sep 25, 2019 6:38 PM

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M2 repeatedly burning F19 fuse

Talbert Simonian 1,802 posts since Nov 21, 2014
Re: M2 repeatedly burning F19 fuse Sep 25, 2019 6:42 PM
Do you have a VIN? There is a tool out there by Snap-On. https://store.snapon.com/Specialty-Circuit-TestersAmp-Hound-Blue-Point--P769765.aspx It is called the Amp Hound. It measure the amperage that is being
demanded.

Noah Mausser 9 posts since Jan 13, 2017
Re: M2 repeatedly burning F19 fuse Sep 25, 2019 6:47 PM
VIN LY8361

Kyle Siebert 4,084 posts since Nov 14, 2014
Re: M2 repeatedly burning F19 fuse Sep 25, 2019 7:11 PM
All these circuits are FET protected in the CHM. What I have experienced with FET protected circuits blowing
the VBAT is a dead short to ground. And if it was a boarder line excessive amp draw it blows the FET, like
excessive amperage due to box lamps wired incorrectly. Not to say that's written in stone but its what I've delt
with.

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M2 repeatedly burning F19 fuse

Sean Evans 461 posts since Nov 12, 2014
Re: M2 repeatedly burning F19 fuse Sep 25, 2019 11:14 PM
I would be looking at the chassis harness where it goes from the cab to the top of the frame, in the area of the
left cab mount, I have seen more harness' chaffed there on the cab mount than I care to talk about.

Timothy Bruner 1 posts since Oct 30, 2020
Re: M2 repeatedly burning F19 fuse Nov 12, 2020 2:11 PM
Me too what a horrible design.

Mic Loschuk 28 posts since Nov 19, 2014
Re: M2 repeatedly burning F19 fuse Sep 27, 2019 1:16 PM
Check the ground splice pack right at headlight. Usually you have a few brunt or melted pins. Have seen a few
of these and they blow out that fuse. Tend to cut out the spice pack and wire the ground directly together.

Kyle Siebert 4,084 posts since Nov 14, 2014
Re: M2 repeatedly burning F19 fuse Sep 27, 2019 6:03 PM
M2/108SD/114SD Harness' and Routing

Chaz Trimble 1,360 posts since Feb 2, 2015
Re: M2 repeatedly burning F19 fuse Sep 28, 2019 1:03 AM
The inline fuses can be a very helpful aid in isolation of these circuits. Also don' forget to check the units
vehicle interface harness A06-87858-007 for the customer to tap into for additional lighting. It will also require
testing/isolation as it uses pin "P" and others listed in the chart above.

Justin Johnson 983 posts since May 12, 2017
Re: M2 repeatedly burning F19 fuse Oct 4, 2019 5:39 PM
Noah Mausser, what did you end up finding out?

Noah Mausser 9 posts since Jan 13, 2017
Re: M2 repeatedly burning F19 fuse Oct 9, 2019 4:15 PM
CSC HAS US INSTALLING A NEW POWER WIRE FROM THE BATTERY DIRECTLY TO PIN P OF THE
CHASSIS MODULE

Justin Johnson 983 posts since May 12, 2017
Re: M2 repeatedly burning F19 fuse Oct 9, 2019 4:30 PM

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M2 repeatedly burning F19 fuse

Thanks for the update Noah. Please let us know how it works out.

Noah Mausser 9 posts since Jan 13, 2017
Re: M2 repeatedly burning F19 fuse Oct 18, 2019 12:49 PM
truck has been running for about a week and a half and have not heard back from customer

Kyle Siebert 4,084 posts since Nov 14, 2014
Re: M2 repeatedly burning F19 fuse Oct 9, 2019 6:13 PM
I take it C4.P is the connector and pin. Hope you installed a 30 amp fuse inline with that circuit.

Jesse Gutierrez 458 posts since Mar 5, 2017
Re: M2 repeatedly burning F19 fuse Nov 9, 2020 3:01 PM
another Issue I have seen with these CHM causing problems is corrosion in the terminals from bad seals etc
causing intermittent issues with the lights.. bad spot mounting the CHM under the cab behind the wheel well

Noah Mausser 9 posts since Jan 13, 2017
Re: M2 repeatedly burning F19 fuse Nov 9, 2020 3:38 PM
Forgot to update results so just going off of memory. Unit did end up coming back. Ended up putting inline
fuse in for each individual output. Unit ran again and blew just one of the output fuses. That gave us our
specific circuit to t/s. Ended up finding a wire in pinched in a mounting screw in the dash area. Wish I had
updated immediately so I could tell you which output specifically and exact location of where wire was pinched
at.

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