Help! Amp draw from fuse position S

Reply Subscribe

Thread Tools

Search this Thread

Jul 17, 2019 | 04:13 PM

OBD_F350

Thread Starter

5th Wheeling

Joined: Aug 2018

Posts: 40

Likes: 0

From: Maricopa County

Help! Amp draw from fuse position S

I have discovered an amp draw from my 1995 F350 460

With truck completely shut down (no key in ignition, doors closed, etc), the amp reading of multimeter in series with battery: 1.170 Amps
Started pulling fuses to identify the problem, and viola! Amp draw drops to nil when I pull the big 50 amp fuse from FUSE SLOT S
My owner's manual of the description of the circuits protected by this fuse, "See fuses 4, 8, and 16. Also, see circuit breaker 12."

These fuses cover a myriad of items, from exterior lights, speedometer, radio memory, instrument illumination, etc)

Working on my truck is a passion of mine, but I do not have the knowledge or experience of a professional.

Does anyone have suggestions on a strategy in attacking this electrical problem of mine? I'd like to get some feedback before I start ripping out the dash and whatnot.

Thank you in advance.

Jul 17, 2019 | 08:41 PM

OBD_F350

Thread Starter

5th Wheeling

Joined: Aug 2018

Posts: 40

Likes: 0

From: Maricopa County

*** Update ***

I have isolated the issue. The amp draw is at fuse #8.

I believe my problem lies within the radio/clock memory. This is just a theory, but when the battery negative is disconnected for an extended period of time (30+ minutes), the radio presets and time of day are still saved.

Jul 18, 2019 | 07:12 AM

rla2005

Fleet Owner

Joined: Oct 2005

Posts: 20,780

Likes: 1,746

From: Kentucky

Fuse 8 has nothing to do with the radio.

Jul 18, 2019 | 08:12 AM

rdayt

Freshman User

Joined: Nov 2018

Posts: 35

Likes: 0

Does your engine compartment light turn off when you close the hood?
Mine shuts off when the hood is 2/3 down.
Seems kinda common.

Randy

Jul 18, 2019 | 01:46 PM

Ddaybc

Elder User

Joined: Jul 2011

Posts: 793

Likes: 2

From: Vernon, BC

Also check your glove box light. It can remain on even with the glove box closed if it isn't "tight" against the stop and you won't see it.

Jul 18, 2019 | 04:00 PM

byronbgs

Tuned

Joined: Jul 2002

Posts: 479

Likes: 12

From: Louisiana

Troubleshoot starting with the easy stuff first. Light bulbs at night get in and wait for all lights to extinguish. If you have Zero lights on and no light glow from the glove box then the light circuits probably good. Next find the Remote entry key module and unplug the connectors. Check the amp meter for current draw. Then find the Programmable Speedometer / Odometer Module and disconnect it ... check the amp meter. If none of these works then do more research.

Jul 19, 2019 | 04:13 AM

OBD_F350

Thread Starter

5th Wheeling

Joined: Aug 2018

Posts: 40

Likes: 0

From: Maricopa County

rdayt - Long ago I pulled the lightbulb from the engine compartment fixture. It had been flickering and working erratically, which annoyed me to the point that I pulled the thing.

Ddaybc - I went and double checked the glove box lightbulb, which I can happily rule out. It's a common issue, or so I've read. Thank you for the suggestion.