Hi Guys,

I just bought a 2000 Discovery II that I thought was having alternator problems. When I went to look at it, the battery was dead and the girl told me it needed an alternator. I hooked up the jumper cables and it started up and ran good, as long as the cables were hooked up. It would cut right off when I took the jumper cables off. So I figured it was definately the alternator.

So I bought it. I replaced the battery and the alternater and now it is not getting any fire to the plugs. It ran fine 3 days ago with jumper cables to the old battery and alternator. Does anyone have any ideas on why it's not firing?

Thanks, Jason

 

If the alternator was bad it would run off the battery.
If the battery is bad it would run off the alternator.
Battery was dead, would not run...bad alternator.
Replaced battery, now it wont run.
(just thinking out loud)
Will it turn over?
Is the new battery fully charged?
They loose charge sitting on the shelf.

 

What about the ECU being turned off by the alarm/security system when the battery was changed?

I seem to recall seeing something regarding that on the DII.

 

the battery is fully charged and it spins over good, but it's not getting any fire to the plugs. The alarm maybe the culprit. Is there any way to check or reset the ECU?

 

Reset the inertia switch on the firewall, black button.
If still no spark then you need a crank position sensor.

 

I tried the ineria switch with no avail. Read another post and said to activate and deactivate the alarm by either the key fob or by unlocking the drivers door 3 times. It just so happens the only key I got with the purchase of the Disco does not work in the door lock. Nor does the fob (looks like broken micro switches on the circuit board). I jiggled the key in the door lock for a while but was never able to unlock it, but I then tried to crank it and it cranked!!! It only stayed cranked for about 3 minutes (and sounded fine) and then cut off by itself. Then would not crank again. It turns over good.
Could it still be the crank sensor if it ran for 3 minutes? Alarm? Please help...

Jason

 

First of all, if the starter is turning over at the correct speed, the only thing that will cut your ECU signal to the coils is a failed cranks shaft sensor, have you checked that yet?

 

Is that a way to check the crank sensor, or do I just need to change it out with a new one?

 

Go to the Rave CD, there is a write up on how to test and what the values should be.

 

Remove a spark plug, hook up the plug wire to that spark plug.
Lay it on the exhaust manifold.
Have a friend try and start the truck while you check to see if the spark plug is sparking.
No spark, bad crank sensor.