[TR] Electrical Gremlin

[terryrs at comcast.net]

Good coffee, good advice, and a fresh morning's perspective.  Beautiful day without snow, flies or rain in New Hampshire.  

So, while my cheap multi-meter had been showing voltage out of the load side of the switch, it apparently wasn't enough.  I did see a drop from the power side to the load side, but didn't know how much the switch might drain, though it shouldn't have drained any.

Anyway, I just bypassed the switch altogether and had an abruptly healthy circuit all the way back to the brake lights.   This was a new switch installed during the restoration, so am with you, Randall, and am going to rig a mechanical switch to the pedal box.

Thanks for your help again.  I think I started off owing you a coffee three years ago.  Two years ago, it was a box of Joe.  What the heck have  I run my tab up to by now????  

Oh, I know.  A gallon of gasoline!

Terry

-------------- Original message -------------- 
From: "Randall" <tr3driver at ca.rr.com> 

> 
> > Both brake lights and fuel gauge not working. 
> > 
> > Power to the brake switch. 
> 
> Assuming that's not a typo, it suggests the problem with the brake lights is 
> not one of power not getting to the switch. Recheck using a helper to hold 
> the pedal down, then check the load side of the switch. I had a lot of 
> switches fail, before I converted to a mechanically operated switch mounted 
> on the pedal box. 
> 
> > Wipers and Turn signals both 
> > work, so the connections to the fuse must be okay. 
> 
> The later TR3s had all separate wires to the 'green' terminals of the fuse 
> block, and all TR2-3 had a jumper between two terminals at the fuse block. 
> So, the connections could be loose/broken, or the jumper loose/broken; and 
> it would only affect some of the 'green circuit' items. 
> 
> > So question. While the schematic shows the circuits for the 
> > fuel gauge and brake lights are separate, do they in reality 
> > share a common green power line, and is that where I should 
> > be seeking the open/short? 
> 
> Nope, those wires join only at the fuse block. 
> 
> > I could tear the wire harness apart to find out, 
> 
> Strictly a last resort. At the very least, I would verify that there is 
> power in the wire (by piercing the insulation with a sharp probe) at one end 
> and not at the other end; before tearing into the harness. 
> 
> Please note that Occam's Razor does NOT always apply ... sometimes there 
> really are multiple problems that just happen to occur (or get noticed) at 
> the same time. 
> 
> Randall