I have the Greddy 60mm warning gauges. My fuel pressure gauge doesn't light up. I have a boost gauge that works perfectly and is wired to the same connections. I removed the boost and wired the FP by itself to see if it was receiving enough power or was getting "crossed over" with the boost gauge, then I tried to switch harnesses to see if there was a problem with these. The boost gauge still lit up and worked fine but the FP doesn't light either way. I've checked all the harnesses and made sure they were plugged in all the way, all the wires look in tact and have not been used prior to my installation.

I bought the gauges off of ebay and Greddy won't replace something that wasn't purchased from an authorized dealer. I don't know if the gauge uses an LED or a bulb for the background. The gauges are brand new, both came in the original boxes and the harness/hose for the fuel tap were still wrapped in the plastic and sealed.

I'm 99% sure everything is wired correctly because it is exactly the same as the boost, aside from where the sensor goes...obviously. Also, the warning light is on because I removed the sensor from my fuel pressure source. The light is always on and dims when I turn on my headlights so everything else seems in order.

Anyone have any ideas on what it could be...or am I just SOL?
Thanks in advance,
Robert

 

If it has a bulb, it can be changed. It's time to find that bulb, get it out and test it.

 

I thought so. I just tried taking the gauge apart, there are two hex bolts and to rubber grommets on the back that I removed. After that there is nothing else, so I tried pulling and twisting of the face and it moves maybe a mm. I'm not quite sure if there's a tool thats needed to remove the face from the back. My brother's Defi gauges are a bit easier to dissassemble (they weren't broken, just looking at them to see if they were similar to the Greddy. Those are very quality gaugtes).
I'll look at it again today at work. Thanks!

 

Are you sure it's supposed to light up? Are there enough wires hanging out of it to support a light circuit?

 

Yes, I'm sure it's supposed to light. I have the same type of gauge just the boost and everything is exactly the same. There's a harness with about 7-8 wires hanging out the back of it. It has the memory capability and a warning light also.

I'll have my bro take a look at it. He uses the Defi gauges, and those are some quality pieces. Get this, my other brother has Autometer gauges for his Mustang that he bought USED off of ebay. He contacted Autometer because both gauges were broken. They sent him basically two whole new gauge kits (the pyrometer and boost sensors and all the wiring).

Anyway, I think we'll be able to figure it out. If not I may have to send it to someone that lives close to one of these dealers...that'll be cheaper than buying a whole new one.
Thanks guys!