My Wifes TF Magna's Speed Alert is giving me hec
When its turned off, or set to lets say 110km/h (open road driving), and you turn off the car,
When you come back to it and turn the key on, it starts again, at 60km/h again.
Is this something i did wrong when replacing the older Sony deck with a newer one (direct plug and play replace) or perhaps a Voltage drop in the whole car, from now having Sub/amp setup???

please help???

I'd be checking the battery. Mine does this when the battery is on it's last legs. - Voltage drop when cranking the engine over
Might also pay to check the alternator as well

could be a voltage drop, if you got a multimeter check your charging system. first try with your amp and HU off, voltage should be around 14.4v idle. then check with the amp/HU on, there should not be much difference in voltage drop

Oh, not cool.
Dont have a multimeter, so cant check.
But im sure the battery is fairly old.

What CCA do people recomend, being the car now has sound system with sub and amp :D

Sounds like your battery voltage is dropping below nominal when you crank the car. Normally when you pull the battery from the car and reconnect it you'll reset the speed alert back to default which is 60km.

500 cca is usually average for these cars, i cant really recomend a battery, everyone has thier own oppinions, depends on your budget ECT. but 500cca is a good base to start from

Depends on how big the amp is and how long you intend to run it for while the engine isn't running, there are some good all round starter/deep cycle batteries nowadays. If you're out north I can recommend Cell tic batteries at Salisbury, if you ask they'll check your existing battery and alternator.

Sorry I'm not exactly North, Live 1/2 way from city to Port Adel, kinda North West.
I think there is a cheap place behind Arndale Shopping Centre, next to the "Don Mortons Marine" Boat shop/mechanics.
and then there is ALCO on Grand Junction, near end of Addison Road, Ottoway.
Might see them for price, anyone know any other places local to Arndale/Port Adelaide

If you can afford it try and get optima Yellowtop, good battery and can handle plenty of draw from a sound system. My car has a Supercharge Gold battery which is meant to be good but i often have issues and i only run 1 amp :/

Check the fuse in the yellow holder contained in your engine bay fuse box, lift the square holder up and pop the fuse

Buy a optima D34 off ebay? $250 In SA, think its free postage too.

Im only running a single Amp. Bridged of course. Running to only one sub (12inch). Setup like all cars ive had before, guess this battery is just more shagged than other cars ones. :(

Check the fuse in the yellow holder contained in your engine bay fuse box, lift the square holder up and pop the fuse

:stoopid:

If this Is the issue or you can't see if it's okay or not..

Grab a spare from the wreckers and give that a go..

SuFz

+1 to the fuse, I ad the same problem when installing a new overhead light and shorted to the body. Blew the fuse and the trip computer went haywire

I would just get a Century battery. I wouldn't bother with those imported batteries of various names, they're the ones that people have troubles with.

So, either:
Hi-Performance 540CCA http://www.centurybatteries.com.au/search/index.php/batteries/ID-50-1385
or
Ultra High Performance 620CCA http://www.centurybatteries.com.au/search/index.php/batteries/ID-49-1385

These are the Century recommendations. Typed in Magna TH in the search, that covers Magnas from 1993-2001. In store when they look it up in the catalogue it will probably specifically state TF, but in any case batteries aren't quite that specific, apart from the terminal layout. The same batteries are recommended for all the third gens and 380's.

If you want to find a retailer, just type in your suburb in the 'find a retailer' part at the top of the page.

as mel has said, these fuses can blow as well in the engine bay, once again, a little cheap $10 multimeter can save a lot of time and work

Not sure why everyone is on about batteries when the basic check has not been done

OP, turn the car off, go back a few hours later, turn on ig but do NOT crank, if speed alert is reset is not a battery issue. If the battery voltage is dropping so low on crank the car would not generally start anyway as most magna owners know a low battery will give all sorts of issues like stalling after start or simply crank with no fire

Not sure why everyone is on about batteries when the basic check has not been done

Based on my own (limited) personal experience. I have a TF in which the speed alert would regularly reset upon starting the engine, for about 6 months before I finally decided I'd better replace the stuffed battery. Mine just wouldn't "not start" the engine just needed a gentle nudge from the starter and it would fire away.

I do like your suggestion, keep it simple :)