Identify relays/auto-reset fueses on front firewall?

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JoeyD
Posts: 37
Joined: Sun Jul 12, 2020 6:23 pm

Identify relays/auto-reset fueses on front firewall?

Post by JoeyD »

Any guidance would be appreciated on identifying the function of the relays/breakers on the d-side exterior front firewall.
Also, any other relays(along d-side frame rail near the transmission), and confirmation of the correct wire-colors on the relays.
A mechanic was trying to determine an intermittent headlight issue, and swapped wires on the two black sealed relays on the bottom left of the pic...I'm not 100% convinced that they were replaced properly.
Tnx.
Stay safe
--JoeyD
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Stay safe
--JoeyD
'95 Safari Sahara 3530
Cummins 5.9
Conifer, CO.
stuplich@ymail.com
Posts: 1146
Joined: Mon Oct 28, 2019 8:51 am

Re: Identify relays/auto-reset fueses on front firewall?

Post by stuplich@ymail.com »

Mel
'96 Sahara 3530, mine since '01
250 hp 3126 Cat, MD3060 Allison
JoeyD
Posts: 37
Joined: Sun Jul 12, 2020 6:23 pm

Re: Identify relays/auto-reset fueses on front firewall?

Post by JoeyD »

Hi Mel.
Sorry, I know how to check voltage/current/resistance/etc, I'm looking for the circuit(s) that the various breakers and the two Bosch-style relays control.
Stay safe
--JoeyD
'95 Safari Sahara 3530
Cummins 5.9
Conifer, CO.
TDJohn
Posts: 552
Joined: Sun Oct 27, 2019 11:34 pm

Re: Identify relays/auto-reset fueses on front firewall?

Post by TDJohn »

This is a guess from memory, I think the silver relay is the horn relay, the other two are likely the headlight relays.
The self resetting breakers are likely (in no order), headlights (not sure if one is for low beam and one for high beam, or one feeds both), wipers, the electric hydraulic pump for the hydroboost brakes system in case the normal hydraulics fail. Again, this is a ruff guess from memory, it would not be hard to pull a wire from each individual breaker, one at a time and see which items I listed stop working.
John
'95 Serengeti, Cummins C8.3-300
Allison 6spd.
CactusTwo
Posts: 70
Joined: Mon Oct 28, 2019 12:06 pm

Re: Identify relays/auto-reset fueses on front firewall?

Post by CactusTwo »

Left relay is for the wipers from fuse7 on ignition fuse panel, right one for added power for rear, marker and clearance lights powered from 20 amp fuse top from chassis hot panel. Circuit breakers....far right with orange wires is for power seat. Next CB black and yellow wires is dash air conditioning high speed fan. That's all I got
Len and Brenda Nugent
Alberta, Canada, fulltimers since 2012
1996 Safari Serengeti 3740 front door, bought in Feb 2019
Cat 3126 300hp, Allison MD3060, VelvetRide suspension
sold 2008 GMC Duramax 3500 and 37' Cedar Creek 5th wheel
CactusTwo
Posts: 70
Joined: Mon Oct 28, 2019 12:06 pm

Re: Identify relays/auto-reset fueses on front firewall?

Post by CactusTwo »

Send a better picture of you under dash/ hood so I can help better. One real BIG point "How could he swap wires when they are still zip tied and covered in dust. They are all real trimmed to fit where they placed from factory....sooooo he is pulling at your wallet!! Just saying!. Intermittent headlights are NOT anywhere in the picture you posted. Headlight switch could be gummed up or has loose wire connectors and number one reason is GROUND wire!! Please someone chirp up about loose ground wires!! I am NOT crazy. Top is a shiny solenoid controlled by key ignition, left side red 6g wire comes from chassis batteries, black 6g wire on the same post goes to "always hot" ignition fuse panel under hood, black 6g wire on other side goes to "when the ignition is on" fuse panel under hood. Black plastic round thing is flasher control blinker "made in mexico it says". I have removed ALL my zip ties and traced as many wires as I could and bought new zip ties (without dust on them) and re tied wires again "without dust on them" Run Forest RUN is my hint of the day to you.
Len and Brenda Nugent
Alberta, Canada, fulltimers since 2012
1996 Safari Serengeti 3740 front door, bought in Feb 2019
Cat 3126 300hp, Allison MD3060, VelvetRide suspension
sold 2008 GMC Duramax 3500 and 37' Cedar Creek 5th wheel
stuplich@ymail.com
Posts: 1146
Joined: Mon Oct 28, 2019 8:51 am

Re: Identify relays/auto-reset fueses on front firewall?

Post by stuplich@ymail.com »

CactusTwo wrote: Thu May 13, 2021 9:03 pm Send a better picture of you under dash/ hood so I can help better.
CactusTwo
Better than this?
Image
Mel
'96 Sahara 3530, mine since '01
250 hp 3126 Cat, MD3060 Allison
JoeyD
Posts: 37
Joined: Sun Jul 12, 2020 6:23 pm

Re: Identify relays/auto-reset fueses on front firewall?

Post by JoeyD »

Tnx for the comments. I had re-tied the wires that the mech had cut/"swapped".
I've now cut all of the ties and started tracing them to the fuse blocks. I was also able to wrangle an assistant...it's easier for someone in the cab to toggle switches while I've got my test leads attached. I can listen for a tone when the circuit is activated.
Tnx agn.
The coach has sat for the last seven years, I'm finding dust in the weirdest of places.
Stay safe
--JoeyD
Stay safe
--JoeyD
'95 Safari Sahara 3530
Cummins 5.9
Conifer, CO.
TDJohn
Posts: 552
Joined: Sun Oct 27, 2019 11:34 pm

Re: Identify relays/auto-reset fueses on front firewall?

Post by TDJohn »

Len,

I agree with what you say and grounds are sure known to be an issue. That said, the headlights are on a thermal breaker, so if there is an overload in the circuit or a weak circuit breaker, it will kick of and on intermittently by in a more rhythmic way. I remember long ago, one of our local fire trucks head a weak self resetting breaker, and about every thirty seconds the whole light bar and a few of the perimeter lights would go off for about 10 seconds and then go back on for 30. Looked funny.

Mel,

I'm guessing what is meant by a better photo, is a photo from a distance, that captures the larger general area, so one can better orient themselves and see more to be able to help identify what is needed in the photo.
John
'95 Serengeti, Cummins C8.3-300
Allison 6spd.
CactusTwo
Posts: 70
Joined: Mon Oct 28, 2019 12:06 pm

Re: Identify relays/auto-reset fueses on front firewall?

Post by CactusTwo »

More a picture of the fuse panel area and line of wires coming from the porthole from under dash
IMG_6608.JPG
IMG_6608.JPG (7.12 MiB) Viewed 5563 times
Len and Brenda Nugent
Alberta, Canada, fulltimers since 2012
1996 Safari Serengeti 3740 front door, bought in Feb 2019
Cat 3126 300hp, Allison MD3060, VelvetRide suspension
sold 2008 GMC Duramax 3500 and 37' Cedar Creek 5th wheel
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