Searched the forums close to an hour and could not find a similar issue. Started yesterday, driving during the day when applying the brakes my guage cluster dims. When brakes are released the guages return to normal dim setting. Anyone seen this before? Video coming shortly..

 

Rx8 cluster dims when braking - YouTube

 

I've never seen that before but maybe it's fuse related. did you run the codes on that cel?

 

It's not a CEL.. its the key proximity light. The guages are from an R3 and that light has been on since I installed that cluster. But as you can see its been 6k since I've replaced it and this just showed up.

 

ah, my apologies. personal fail. Well if it's onset wasn't until 6k was put on it I don't think it was an installation issue. Bump for interest then, I'm stumped.

 

grab a multimeter and measure the voltage at the input power to the cluster. Hit the brakes, measure the vdroop and report back. Is it worse if you have the headlights on?

 

Check the Wiring Loom in Trunk LID....it could be the start of 'a' failing small harness.

Also could be caused by LED's 'if' you have them.

This is the new Part Number F151-67-06YC Trunk Lid Harness..

Put the Part Number in Search Box above and Search....I will sticky 'the' thread.

 

Do you have the proper size battery in the car and is it up to snuff? Check for corrosion on the terminals and check for continuity on the cable going from the battery to the alternator. And the battery to the fuse box. Also check for alternator output. Easy thing to rule out first before you go digging deeper elsewhere.

Chances are it more than just the cluster and you haven't noticed. Try it with the dome light on. Or the parking lights on. See if they dim also.

 

Thanks for the suggestions.

I have a voltmeter and battery tester, I will carry them all out this weekend.

I knew I was getting a short somewhere.. First I did a walk around and I saw some moisture building up in the passenger taillight.. again.. took care of that and the problem went away.

I'll do all the tests in my shop but it may be a while before she hits the road again with winter weather finally kicking in.

 

you have a R3 instrument cluster in an S1 model?
I thought the ob2 stuff was much different?

 

I was wondering that too, but the cluster is mainly HSCAN stuff which is pretty standard, the big changes in OBD2 implementation between the two series is that the S2 utilizes the MSCAN for non-critical messaging (radio/etc)

 

do you have aftermarket tail lights or blinkers?

 

WAIT.... you can change out the clusters!?!?!?!??!!?!??!!?!??!

i was told it wouldnt work in a thread i made a year or so ago....

holy bageebus... any comments on the install? fairly straightforward? please share

 

uh ... are you not following the thread? clearly there is an issue. And we haven't ruled out if it was caused by the swap or not.

 

are YOU following the thread?

clearly it worked for 6k miles...

i was told it wouldnt function at all. Is this a problem with the cluster? possibly, its probable, since this isnt something seen on S1 clusters regularly... Though, it looks like it can be overcome, since it did work for 6k miles.

 

that means absolutely nothing. Electrical anomalies can happen at any time.

 

Have you tried reinstalling your original cluster? Any changes?

Also any other electrical modifications done to the car, no matter how small?

 

the cluster is critical for engine performance. If the fuse to the S2 model cluster blows for example--it will not even crank over. The starter will not work.

 

check the brake light bulbs, could be a bulb shorting and causing that, myself I will first look there, and try to disconnect them and see if the problem is still there, if yes check the wiring harness in the trunk. let us know what you find

 

i hope it is a problem that can be overcome.

I wonder if the moving redline works?

 

Still in the process of checking all your suggestions but I'll add one more fact to the table.
The only time my cluster (and stereo) lights blink off when i hit the brakes, is when my dimness setting is at 50% or below. Full brightness yields no issues.
Yes my taillights are all led except for the blinkers. My interior lights are all led as well. My headlights have the led parking lights.
My cluster wasn't issue free from the install, my fuel level guage does not read correctly so when i get around 200 miles to the tank i refill her. Also the key proximity light is always on.
Tonight I will have time to run some of your tests and suggestions. Thanks

 

still going with the LED taillights as the culprit

 

Funny story for ya: I'm driving down the hwy for a few hundred miles to track my 8. I notice the console with the temp is dimmer than I like, And I know something's up. I don't drive it everyday, so I don't look for the cause very hard.

A year later it dawns on me that the rheostat for the dash lights is not on an indent, but in the scroll up or down place. I think what happens is it gets dusty, so when hitting bumps, etc. it shorts.

Turn your left roller rheostat all the way up until it snaps on full, and see if that helps.

 

^ really???

 

Had some free time and swapped it back to my original cluster and the issue has disappeared.

I may just leave it this way; kinda tired of the poor fuel guage accuracy on the R3 cluster. (ran out of gas once right after the install)

Thanks everyone for your suggestions