| |
Click on image for the lowdown. 
====
| | | Forums66 Topics128,049 Posts1,055,701 Members48,426 | | Most Online14,466
Apr 26th, 2026 | | AD Chevy Trucks  Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
Lots of work on Brad's part ... pure enjoyment (and references) for you!
| | THANKS!
For helping keep this great
old truck web site
on the Internet for over 30 years! and not clogged down
with Ads!  Again, thanks!
| | | | Joined: Jun 2009 Posts: 149 Wrench Fetcher | | Wrench Fetcher Joined: Jun 2009 Posts: 149 | Hi everyone,
This question may seem elementary, but, what is the main power source to cab?
I have found a wire (comes out of the firewall near the battery) that when I connect to the battery, I get power to the cab. The only problem is, this wire is always hot (even with the ignition off) and I'm guessing will drain my battery.
Anyone know how to avoid this or know which wire should be connected to my battery? Or is the cab always supposed to have power to it even when the ignition is off?
---Casey
Last edited by REAL_RAT_FINK; 03/19/2010 6:43 PM.
| | | | | Joined: Jul 2004 Posts: 5,708 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 5,708 | Casey,
I see your profile indicates a '58 rig which I'm not real familiar with. A 'typical' setup for many early rigs used a ammeter in the dash. The output of the charging system was on one side of the ammeter while the other side was connected to the battery via a large terminal on the starter.
This results in power to the cab continuously which is common. Power for any accessory, the ignition or any other item would be on the switched side of the ignition switch which would be powered by the charging system side of the ammeter....hot all the time (from the battery).
The ignition switch is the 'master' that is always powered and passes it along to ignition and accessories only when turned ON!
Your truck may make the connection between charging system and battery in the engine compartment. I believe how this was done in later years. Regardless of that, there will always be battery power inside the cab which is controlled by the ignition switch...the battery side of that switch will be hot all the time.
Stuart | | | | | Joined: Jul 2001 Posts: 3,887 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Jul 2001 Posts: 3,887 | you need to find out where the other end of that wire goes and determine if it should be hooked to anything, the shop manual wiring diagram is a good start
from feeble memory, there should be a wire from the starter terminal that the battery + hooks to, that goes to one side of the ammeter - from the same post on the ammeter there's a wire to the ign sw that supplies power to accesory stuff when the key is on only
Bill | | | | | Joined: Dec 2006 Posts: 1,464 Shop Shark | | Shop Shark Joined: Dec 2006 Posts: 1,464 | Casey; Does your truck still have the ammeter in it? I can't find a wiring diagram for a '58 but HERE is one for a '55. The wire on the starter terminal goes to one side of the ammeter. The other side of the ammeter is what feeds the "loads" which include the ignition switch, light switch, and brake-light switch (which are all fed by an "always-hot" lead) | | | | | Joined: Jun 2009 Posts: 149 Wrench Fetcher | | Wrench Fetcher Joined: Jun 2009 Posts: 149 | Thank you for your replies. I believe I am using the same wire that originally connected to starter (with big terminal on the end). So I have the right wire, but for some reason, I have power to cab and accessaries when the keys are pulled out of the ignition. From the info presented, I think I just need to see what is happening under the dash. I'll find out and post any problems---
Last edited by REAL_RAT_FINK; 03/20/2010 12:37 AM.
| | |
|
|
| |
