I'm installing mechanical oil and boost pressure gauges in my '11 Silverado. Where is the best place to get power for the gauge lighting? I'm running automated Sport Comp gauges which have LED lighting. It would sure be nice to tie them to the cluster lighting circuit and have them dim with the cluster. Though I just now thought about the LED's maybe aren't dimmable. I know there are plenty of trucks out there with these At pillar gauges. What did y'all do to power your gauge lights?

 

Not much interest in this thread, it doesn't look like. I found the answer to the question: the instrument cluster lighting circuit is Circuit Number 230, powered from Pin C1 of connector X1 on Fuse Block I/P, which is the fuse block on the left side of the dash. Connector X1 is the big one on the back of the fuse block. I've removed pin C1 from it, and called the local dealership to see can I get a replacement pin. That way, I can cut this one off; run a second wire to the A-pillar; solder it and the original wire from Circuit 230 together; run a short lead to the new wire end terminal; and crimp it on. Then put that terminal (pin) back in Connector X1 and there you have it. But the counterman couldn't find the wire end terminal in the parts catalog!

Anyone know where to get them?

 

Try Mouser. www.mouser.com They have virtually all of the various Delphi connectors in stock. (brand name this week for those I think is Aptiv) You'll need to know what "series" that is, butt if you download the catalog and look through, shouldn't be too hard to figure it out.

 

You can also look up terminals on the Aptiv website, they have a pretty good catalog/search system. Aptiv is the new name for Delphi parts (at least the electrical/terminals).

https://www.aptiv.com/en/solutions/c...rs?language=en

 

Thanks, y'all. I wound up stripping a little bit of insulation of the power feed wire a little ways behind the wire end terminal and soldering a feed wire for the new gauges' lighting to it and locking the terminal back into the connector. If you zoom in on the photo, you can see the joint wrapped in heat shrink and the brown wire with white tracer leading to the A-pillar.

I found the accessory connector on the EMBC junction block (next to the brake pedal) and used the ground pin there. I stole the wire terminal and a short pigtail from a wreck I have; I'll install it in the proper connector housing when that arrives.


Here's the finished A-pillar with boost and oil pressure gauges. I'll have to wait until I get the trans rebuilt to fire it up and check gauge and lighting function.

I brought my original A-pillar to the local parts store where they mixed up a custom color vinyl and plastic dye to match it. I've owned this truck for 12 years and I never noticed the A-pillar covers have blue specks over the gray. The new A-pillar is a very close match but doesn't have the blue specks... I DID think about trying to mist them on, but figured I'd probably make a mess of it. If I never saw them in 12 years, I guess nobody will notice their absence now.

 

Here's what the underside looks like:


As can be seen, my transmission is out of the truck. I have another thread going about that. That made access to the oil pressure sensor easy. My oil pressure sensor was bad, so I replaced and relocated it. I needed a place to connect the oil pressure tubing also, so I bought this sensor relocator block with two 1/8" pipe connections. This turned out to be a little bit of a PITA, even though it looks perfectly simple. The sensor threads are metric, just like they're supposed to be, M16 x 1.5. I expected the 1/8" pipe threads to be NPT (National Pipe Taper). Instead, they're 1/8" BSPP, which stands for British Straight Pipe Parallel. I had no idea what that is. Fortunately, a machinist friend of mine clued me in, but I then had to go on a treasure hunt to find a BSPP plug for one of the holes; and an adapter to go from BSPP to NPT for the other. BSP fittings do not rely on the interference fit of the threads to seal like NPT threads do, they have a flange and an O-ring and seal against whatever they screw into. In this case the ebay relocation block. We'll, that part is oblong in shape. Its taper starts very close to the 1/8" BSP holes. HOPEFULLY there's adequate contact with the O-ring to make the seal. I added pipe dope to the threads hoping that will provide an extra layer of security against oil leaks.

I extended the sensor harness by cutting the connector off with a little bit of wire attached and soldering 17 or so inches of wire. I wrapped the extended harness in fabric tape just like the factory, then inserted it into that black plastic "wire management tubing" GM uses for harnesses. I then used spark plug wire woven heat tubing to protect it from the nearby header, which is about 3 or 4 inches away from the harness at its closest.

I gave the vinyl tubing the oil pressure gauge came with a similar treatment. First, I inserted it in a length of rubber vacuum hose to protect it from abrasion. Then ran it through the same black corrugated wire management tubing; and where it goes under the header, I used the same plug wire tubing. That stuff comes with heat shrink that get slid over the ends to secure the woven tubing and prevent fraying. I ran the tubing forward from the fitting, alongside the motor mount bracket, and through the firewall in the main harness boot that's more or less under and to the outside of the brake booster. Then it goes up under the dash and into the A-pillar. The boost gauge follows the same path from A-pillar to engine compartment, but then follows the power supply cable that feeds the underhood fuse box across the firewall before turning back and down to connect to the back of the blower. There are three 1/8" NPT ports back there, two in the blower case itself and one in the manifold. Whipple's tech guys said any of those ports would work for a boost gauge. I chose the one in the manifold.

 

Here's the finished product. I expected the backlighting to match the factory cluster, but it obviously does not. I may have had a choice of green LED backlighting... I forget. Frankly, I prefer the white, but it would sure look better if it all matched. Truly ideal would be to change the cluster to match the gauges.... Oh, well.

 

You can change the cluster backlighting

 

Thanks for doing the research and sharing your findings. I think your contribution for providing an answer to this will definitely help others!


Thanks,
Art