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Discussion Starter · #1 · (Edited)
I finally got around to installing my VEI boost gauge, using blockheads vent pod. Great product!

I'm naturally lazy and since the installation is all on the far left side of the car I wanted to find appropriate sources for all the necessary connections on the left side of the car.

So, after finding these I thought other members might find the following useful.

For the +12V ignition switched source (red wire on the VEI gauge) I found a spare fuse slot in the fuse block in the driver's side footwell:
Electrical wiring Cable management Electronic engineering Electronics Electronic component

This is an unused slot originally intended for the rear wiper (wagon only in NA). It's marked as such on the inside of the fuse block cover.

Our cars use low profile mini fuses and I was unable to quickly source any taps, so I made my own using a spare 10A fuse. The fuse block contains 3 spare fuses so you could use one of those in a pinch, but be sure to replace it first chance you get. I didn't have any fuses lying around so used the smallest amperage fuse that was a spare in the car, the 10A one. A 5A fuse or even lower would have been fine, as the VEI gauge is only rated as drawing about 0.2A max.

I used a razor knife (Xacto) to partially remove part of the plastic on one leg of the fuse:
Red Electronic component

Then I soldered my power lead to the exposed fuse leg:
Wire Close-up Electrical wiring Macro photography Cable

Then I plugged the custom made fuse tap in:
Electrical wiring Cable management Electronic engineering Electronics Electrical network

If you attempt this, pay particular attention to the orientation of the fuse. Make sure the fuse is properly oriented, with your wire coming off the top, as within the fuse receptacle there is only one electrical contact. It's the lower side and this is the source of the ignition switched +12V.

It will still work if you plug your tap in upside down, but the fuse will be bypassed and you won't have that protection.

It does require some soldering skills but the beauty of this approach is that the fuse and tap are one and the same. It will require modification to make another if the fuse ever goes, but if installed correctly with good solid, well insulated connections further down the line that should really never occur.

For the dimmer switch wire (green wire on the VEI gauge), I needed to find a +12V source that is switched by the headlight/parking light switch. I found that source going into the Panel Illumination swtich. This is the center switch located down low, above the driver's left knee, between the Headlight Level Adjustment switch and DSC Off switch.

I took the switch out by reaching in behind and up and feeling around the back of the three switches. I identified the middle switch, then depressed the tabs on top and below to free the switch to it slide out. This is easier than it sounds, but some finger strength is needed and I did have to get down into the driver's foot well.
Vehicle Vehicle door Car Steering wheel Steering part

The wire I wanted is the solid green wire at the corner of the connector, with the solid black wire (ground) next to it:
Vehicle Technology Car Auto part Electronic device

In the picture above I've already tapped into the green wire using an insulation displacement tap (available from most hardware or auto stores). I used the 18-22 gauge taps as the wires are quite thin.

If you're not familiar with the use of insulation displacement terminals have a qualified mechanic do this for you, or study and practice with a couple before attempting.

Somebody who is really dexterous and has three hands could also have connected the ground (black wire on the VEI gauge) to the black wire next to the green wire on the connector. I couldn't because the small amount of slack on the harness didn't allow enough room to maneuver to get the other tap into position together with the tap wire.

Instead, I took out the DSC Off switch (same process as above) and attached my ground connection to the black wire on it's connector, using another insulation displacement tap connector:
Technology Vehicle door Vehicle Electronic device Switch

I could also have grounded the gauge by loosening a bolt that screws into the chassis somewhere down in the foot well, but as I said I'm lazy. It was far easier for me to pop out the DSC Off switch and connect to that than put a spade terminal on the end of the wire and then squirm under the car with a socket and ratchet, undo a bolt (after checking it's a good ground with a meter), slip on the spade terminal, reinstall bolt, etc, etc.

Plus, to me, tapping into an existing wire is more elegant than clamping under a bolt somewhere down near my feet.

Lastly, a pic for those people that want to see it installed (same as many other pics already posted):
Speedometer Gauge Tachometer Measuring instrument Auto part

Standard disclaimers: YMMV, and I'm posting this for information purposes. If you attempt this you accept all responsibility and consequences. Use the proper tools and taps, and make sure all your connections are solid and fully insulated. You DO NOT want to go into the electrical system if you're not skilled in proper techniques. An electrical fire is a nasty, nasty thing.

1,334 Posts
Discussion Starter · #4 ·
didn't you buy the pod like 2 years ago? :D
Yes, at least two years ago. It was just after you started making them, as an alternative to that other guy who took our money but never delivered.

Your pod is great quality and looks almost factory, the only thing giving it away as not quite factory is the mounting location. Still far superior IMHO to a pillar mounted or steering column mounted pod. Mounting it in one of the center vents was also not an option for me, as that looks less "factory" than the vent pod.

Other things to note about the vent pod install. Drilling holes through the heater vent was a bit of a pain. Couldn't use a power drill from above due to the windshield, and trying to drill a hole from below looked like a nightmare.

I had a small hand held drill chuck but it only holds bits up to 1/8", so after drilling two 1/8" holes I had to use a small rat tail file to enlarge them to fit through the wires and vacumm/boost line.

Feeding the vacumm/boost line through the firewall was a royal PITA. Taking the battery out and having a helper made it less of a PITA. Took both of us digging and pushing for 10 minutes from opposite sides of the firewall with a long thin screwdriver and WD40 to make a hole through the rubber "potting" material they used to set the harness in place.

That was a pretty thick chunk of rubber to go through. The WD40 made it a bit easier.

Glad that install is finally over with!
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