Gen1 light/battery wire routing question (wire lead 8-RED-2A sxl)

[Badwheel]

Hi, new to the Forum and how it works. As best I could I have reviewed the TMs, and searched multiple threads on the topic. What I have is a running '86 CUCV with new batteries and rebuilt alternators. My situation is that the GEN1 light continues to stay on after running. I know there can be more than one reason for this but am trying to eliminate any thing obvious. This vehicle was a fire truck in its previous life so has quite the set of wiring challenges. Here is my question though...my vehicle has the 8-RED-2A (SXL) routing from the Eng Wiring Harness Block to the #2 post on the Positive Terminal Block. From most of the images and diagrams I have reviewed it seems like it should be routed from the Eng Wring Harness Block to the negative terminal of the rear battery. I am wondering if this could be the source of my GEN1 light issue? I'll try and attach an image, Thanks

BTW the vehicle is an ex-firetruck with electrical components both added and subsequently removed for auction...I'm sure you have seen it before.

 

[Barrman]

The CUCV wiring is very unique but once you get in the zone of concentration and pay attention to it. They are really kind of neat. I had to think about what you wrote in CUCV instead of regular wiring language.

The front battery is charged by alternator 1 and that 12 volts is what runs the truck. The rear battery is charged by the passenger side alternator and is only used for starting and glow plugs in stock trucks. Plus of course the slave cable and military radio power.

However, the 12 volts for the truck is not pulled from the positive terminal on the front battery as you might intuitively think. It is pulled from the smaller wire on the negative terminal of the rear battery. That smaller wire (The SXL you mentioned) should go directly to the small 2 post terminal on the firewall near the brake booster and above the glow plug solenoid. Any other routing will cause issues and probably the GEN 1 light to come on as you mentioned.

Verify your SXL wire goes to that terminal and only that terminal.

 

[Badwheel]

That smaller wire (The SXL you mentioned) should go directly to the small 2 post terminal on the firewall near the brake booster and above the glow plug solenoid. Any other routing will cause issues and probably the GEN 1 light to come on as you mentioned.

Verify your SXL wire goes to that terminal and only that terminal.
[/QUOTE]


Thanks Barrman... I'll take a picture of the truck when I can...out of town. But I think you are confirming what I believe could be wrong. Forget the red line for the moment what I should have drawn was this ...what I have in the truck is in blue (small red wire as you mentioned, spliced into blue near the fire wall), what I think I should have is in green to get the front battery to charge.
Thanks again

 

[Barrman]

Correct. Your green routing is what you want without anything else.

 

[Badwheel]

Barrman...Thanks! Other than not charging the front battery...does it surprise you the vehicle doesn't have other electircal issues with that routing? Just curious