Red arrow light in Tachometer?

[Silveresrty911S]

Just wondering what the red arrow light in my tach is, it seems to come on only when under acceleration. Thanks in advance.

Also, what should I expect to pay for a good paint job, not the most expensive.

Thanks, Rick

[Don Plumley]

It's an upshift light. I've learned to ignore mine. Read about it in your owners manual

[marcesq]

Rick:

Appearently, who ever did the conversion put a Carrera tach in the car. The upshift arrow was not part of the '77 package.

FWIW.

[Don Plumley]

I guess it makes sense because he has a 3.2 which has the DME for that tach...

edit: I don't know if a 77 tach would work with a 3.2 installation. Anyway, if you really want to disconnect it, there is a thead or two that talks about disconnecting a wire at the DME.

edit2: Sorry Marc, didn't realize you had a 3.2 conversion - I'm just all reaction and no brains...

[marcesq]

Don:

What I learned by experiment (because I didn't want to buy a tach) was that the DME tach wire (black/violet) replaced the same wire on the 2.7 tach and the tach worked just fine.

[Don Plumley]

I see - thanks. Though you gotta hand it to the guy that did the conversion, it's very complete to include the crazy shift light!

[marcesq]

. . . . or wanted to keep a perfectly good tach and sell a new one, or didn't know any better.

Rick:

I will go back and find my wiring diagrams if you want to know which wire to pull. It is either black or yellow I think and has a pin that plugs into the connector in the rear of the tach.

[Don Plumley]

Here's a pretty good thread on the subject.

I was going to discconect it, but like I said, I just learned to ignore it. I kind of like having everything work. The PO put a small Porsche shield over the light, but in the dark the glow was distracting. I liked the gauge face clean - if you follow this link it will bring up a photo of my dash before I removed the emblem and turned my gauges - it looks like this now.

[marcesq]

Great pics Don . . . there is just somthing about that those gauges that inspire me to strive for high noon

[Silveresrty911S]

Don & Marc,

Thanks for the replies, a buddy of mine said it might be a shift light, but it comes on way before a shift point.

Marc:

If you can find your wiring diagram I think I would like to lose the red arrow. It wasn't working the day I bought it or Sunday. Just started working when I got in the car after work. Must have been the twisties Sunday afternoon.

Thanks, Rick

[weber92037]

It's probably the CASIS light. Computer Assisted Shift Indicator etc., etc. Mine works about half of the time. I havent figured out why it is intermittent and I never pay any attention to it anyway. It seems to want me to shift at much lower RPMs than I want to. It's supposed to tell you to shift at the most economical point. Discussion in the Carerra owners manual.

[Ove]

Hi, Rick,
Haven't seen this arrow light on a Porsche before, but I have one on my M@zda. Removed the bulb the day I bought the car, as the light turned on at 3000RPM. From what I hear your light should also come on early, so it is there for fuel economy reasons! Lets hope the guy at Porsche who put it there got fired

Anyway, why not put a REAL shift light in there and set it to come on just before you reach the redline? Involves more work than just removing the bulb, but would look more professional since the light is already there

Found this at http://www.dalhems.se under electronics, shift lights:

[RickC]

That little arrow light is the upshift light. 3.2's had them in the 1980's to try and help with EPA gas mileage numbers. They indicate the way to drive for best miles per gallon. Contemporary VW's had them also. It was mostly a trick to get better numbers from the EPA. Nobody followed them then, and today, few people seem to care about mileage.

[rvanderpyl]

The light indicates the most economical point to shift. It wasn't put there because Porcshe thought it was a good idea, but rather because the US goverment regulations on fuel economy allowed the testing procedure for fuel economy calculations to be modified to use an indicated shift point rather than the goverment mandated ones, if the manufacturer included a visual shift indication.

[island911]

I hear that the stupid upshift arrow isn't completely stupid; at wide open throttle, the arrow will tell you when to upshift for maximum acceleration.
Try wide open throttle, and let us know if this is true. I'm also curious if it econo mode gets shut off during wide open throttle.

[Tim L]

Yes, at WOT the shift light comes on just before the rev limiter kicks in.

Tim

[marcesq]

Rick:

It should be the black wire attached to the #1 terminal of the tach. There is a black/violet wire on the #2 terminal, and a red/black wire to the #5 terminal.

Pull the black wire, and wrap it up just in case, and the little arrow should go out for good.

[Silveresrty911S]

Thanks for all the info, this board has a great wealth of information. Thanks to all @ Pelican and the members here on this BBS for sustaining this site.

Marc, I'll try the terminal 1 and see if that does it. It was intermitent last night when I was getting on the freeway and had my foot in it for a bit, then it stopped working the rest of the way home. I'll fix it for good!


Thanks,Rick