URGENT HELP. MX5 not starting. has charged battery

Mr Morlock · Postby **Mr Morlock** » Sat Jan 29, 2011 3:49 pm

connect the battery and try the horn or main lights- if they are dull or do not work it is most likely a dead battery. If the lights are ok and the starter motor will not engage most likely the fault is in the starter system- a Haynes is useful. You can try a jumper lead with correct technique or take out the battery and get it checked. Batteries should be AGM type - see posts on this. Fast charge on AGM's can kill them. A full charge on a trickle charger is going to take all night at the least I would say.

Steampunk · Postby **Steampunk** » Sat Jan 29, 2011 6:14 pm

So you don't hear the starter solenoid click at all? If so, then due to my limited knowledge regarding dead electrics, I am agreeing with you on the imobiliser, but then again, if THAT works properly, shouldn't the alarm go off when you try to start it?
Is the on/off switch the same as a bypass switch that is hidden away somewhere?

Have you tried jump-starting with a car whose batteries are DEFINITELY in good condition? Just because accessories work, doesn't necessarily mean the battery has enough juice to fire up the starter, ie. starter solenoids don't like it if it doesn't get fed enough volts, unless I am mistaken, under 10volts is not enough.

zossy1 · Postby **zossy1** » Sat Jan 29, 2011 6:24 pm

It is definitely your Mongoose.

Find your remote and switch it off, or rip it out and re-form your ignition harness.

We have this problem all the time with wrecks we buy that have aftermarket alarms / immobilisers.

snshami · Postby **snshami** » Sat Jan 29, 2011 6:29 pm

zossy1 wrote:It is definitely your Mongoose.

Find your remote and switch it off, or rip it out and re-form your ignition harness.

We have this problem all the time with wrecks we buy that have aftermarket alarms / immobilisers.

I am not disputing your diagnosis but wondering what your reasoning is. What does the immobiliser do when the battery loses charge?

zossy1 · Postby **zossy1** » Sat Jan 29, 2011 9:31 pm

The bloody things (many of them anyway) have a failsafe. When they lose power, they switch themselves on and stay on when power is reconnected. This is to prevent thieves from being able to disable the alarm by disconnecting the battery and reconnecting it. Most also have a battery backup which will automatically activate the alarm when power is lost.

Every unit is different, but they are universally annoying when you are missing the remote.

Jeo · Postby **Jeo** » Mon Jan 31, 2011 10:07 am

So sorry, but your logic was that the car started once the battery was fully charged so it must have been the alarm? I don't follow.

Steampunk · Postby **Steampunk** » Mon Jan 31, 2011 11:06 am

Jeo wrote:So sorry, but your logic was that the car started once the battery was fully charged so it must have been the alarm? I don't follow.

x2
The alarm/immobiliser did what it's supposed to do.
Buying a car that has the aforementioned fitted and NO remotes is never a good idea.

geofiz · Postby **geofiz** » Mon Jan 31, 2011 1:45 pm

You can still get remotes for mongoose alarms, and they are actually quite good. Many years ago I used to work with the WA disrtibutor for these. If you need a remote, let me know and I can try to contact him and see what you need to do to get a replacement.

zossy1 · Postby **zossy1** » Mon Jan 31, 2011 9:08 pm

markis wrote: i was able to bypass the mongoose and she started first go

Glad to hear it

Yes, the alarm was just doing its job. They are good units when they are working as others have said - but I'm still glad to hear that your car is mobile again!