Community Forums

Timaz · 01-20-2020, 03:37 PM

I keep blowing the Fusable link on Engine Battery. What size fuse should this be? and what is it for?
I have the same type for the House batteries and it is 20 amp fuse.
The first one I replaced for the engine battery was 10 then a 15. I just want to know what size it should be and what it's for.
See pictures

twinboat · 01-20-2020, 03:54 PM

It depends on the wire gauge. If you can find that, you can fuse up to its rating.

Fuses protect the wire from overheating and melting the insulation, and then starting a fire.

Timaz · 01-20-2020, 04:04 PM

Quote:

Originally Posted by twinboat

It depends on the wire gauge. If you can find that, you can fuse up to its rating.

Fuses protect the wire from overheating and melting the insulation, and then starting a fire.

Do you know what it should be powering?

CountryB · 01-21-2020, 06:01 AM

Looking at the 2001 Dynasty wiring diagram, the only fuses (not fusible link) I see near the batteries are two 15 Amp for ECM. Everything else (except house 12V panel located inside) uses circuit breakers.

RobRoy · 01-21-2020, 07:22 AM

Looks like you’re in good hands and as stated by others I don’t see a fusible link in the electrical diagram nor the pictures posted, I do see an ATC style fuse holder for a 15 amp fuse.

Fusible links are used in most cases for protection from the battery supply to the fuse holder or the power distribution center.

The purpose of my post is take a close look at the blown fuse ….how the fuse has blown and how it looks can be very helpful in a diagnosis.

If the fuse blew like a old camera Flash Bulb ( remember those?) and no signs of heat… just a blown wire in the fuse? ..then the circuit was quickly and severely overloaded like perhaps a power supply wire shorting to ground.

On the other hand if the fuse looks to be discolored and the fuse wire end melted the this would indicate the fuse was most likely overloaded over a long period of time and most likely will be a component connected on that electrical circuit and is starting to fail.

Happy Hunting

HJLowell · 01-21-2020, 07:28 AM

CountryB got you covered

1. Engine ECM
2. Transmission ECM

They should not be blowing???
Further investigation needed.

Timaz · 01-21-2020, 02:19 PM

I don't have any warning lights or engine or trans problems. Could this be charge wire for the battery?

CountryB · 01-21-2020, 02:32 PM

Unlikely. A 15A or 20A fuse would be too small for a charging circuit.

Timaz · 01-21-2020, 02:58 PM

Quote:

Originally Posted by CountryB

Looking at the 2001 Dynasty wiring diagram, the only fuses (not fusible link) I see near the batteries are two 15 Amp for ECM. Everything else (except house 12V panel located inside) uses circuit breakers.

Hi Mike, I have a ISC engine the wiring diagram is for a ISM or ISX...don't know if they are the same.
I still have my HWH air leveling controller out to HWH being fixed...but I can't think of anything there that could being blowing fuses. It seems to be a fast pop because there is a big gap in the fuse. Only happens after the key is turned on.

How many amps to the air valves pull?

Timaz · 01-21-2020, 09:08 PM

Quote:

Originally Posted by Timaz

Hi Mike, I have a ISC engine the wiring diagram is for a ISM or ISX...don't know if they are the same.
I still have my HWH air leveling controller out to HWH being fixed...but I can't think of anything there that could being blowing fuses. It seems to be a fast pop because there is a big gap in the fuse. Only happens after the key is turned on.

How many amps to the air valves pull?

Following this thought I put in a 20 amp fuse (the same as the house batteries)
That was it. I have the travel valves jumped to "Keyed power". (while the HWH controller is out being fixed) I started the coach and when the air came up it came right up to the ride height...and no blown fuse.

Thank you guys for the input.