Have a 2003 discovery with 136K miles. 2 weeks ago would crank over, sometimes would start other time would not. Totally hit and miss. Finally would crank but would not start. Had it towed home.
Replaced the CPS, that was a PITA! Finished the job, went to start the elephant, and then.....wait for it...
WOULD NOT CRANK! Felt like Chevy Chase on Christmas Vacation!

After getting some pointers from many forum posts, I checked the following:
1. Check and replaced the battery
2. Checked every fuse
3. Cleaned all grounds - what a mess!
4. Cleaned and ensured the battery terminals were good and tight
5. Reset the body roll switch on the passenger firewall
6. Locked and unlocked with the remote
7. Checked (hard to do with one person) the voltage to the starter trigger wire - didn't see any voltage, but all I had was an old analog voltmeter, so I gave up and went into the air conditioning and passed out.

Next day...revived, and thought it through with a clearer head and jumped from the starter trigger post to the battery with the ignition switch on, and the elephant started right up. YAY!

OK so my next issue is why aren't I getting 12 volts to the trigger wire?
Checked fuse #23 fuse and it's OK.
Are there any additional fuses or relays between fuse #23 on the driver side fuse box and the trigger wire?
OR do I start looking for a new ignition switch.
Any help would be greatly appreciated. Thanks for reading....

We love this rig!

My elephant

 

Check the Ignition relay,

 

Basic circuit analysis now - do you have the Rave? If not, download it and look at the wiring diagrams, start checking for voltage along the way. BTW, my memory is you need to lock/unlock with the remote or key 3 times.

 

Starting or not, that is a good looking Disco 2!

 

Where is the ignition relay? Under the hood? I will find the rave download.
I can't temember how many times i performed the lock / unlock routine. I will try that again and cycle it 3 times.
.

 

Wow, she is VERY nice! Hope you get the starting issue fixed. Sounds like bad ground or loose/corroded connection.....

 

Bloody knuckels

 

Post up again once you have the Rave downloaded.

 

Pretty sure you found the reason it won't start.

 

Found that the Viper car alarm was causing the no start condition - not sure why, and don't care cause when it's cooler in South Florida it's getting removed and going in the trash. With the ignition switch in position 2, I jumped from the solenoid to the battery positive lead and she fired right up. Found the position 3 ignition wire with a test light, and (temporarily) ran a wire from that wire to the starter. Although it's a "bubba" it's routed nicely, and looks good and works.