Hi All,

I picked up a Disco II about 6 months ago. First 4 months were a dream. Shut off on me 10 feet from a LR Dealership in Atlanta (would crank not start), then got it towed up to my shop. Originally, the shop replaced the fuel pump injector and the inertia switch. This, of course, was not cheap, but I did not know how to diagnose it at the time. About a month later, my car would not start again. I had to leave it for the afternoon, but when I picked it up that night, it started no problem. Now about 5 weeks ago, it shut down on the highway. Full loss of power steering & power brakes. I got it towed back to the shop. They replaced the crank shaft position sensor and I picked it up and drove it home no problems. I left it sitting for about two weeks, tried to take it out for a spin and voila, it will crank but it will not start.

That all brings us to today. I have tried just about everything I can think of. Using my diagnostics tool, I tested the Disco and got 3 error messages:

• Battery Voltage not plausible, Drive Cycle A
• Air conditioning compressor power stage fault, Drive Cycle A
• Anti-theft alarm serial link fault, Drive Cycle A

I tried to jump the Disco II due to the battery voltage, did not work. I brought the battery into the Advanced Auto Parts and had them test it, all good there. Tested the basic fuses using a multimeter. Replaced the fuel pump relay. I have purchase another crankshaft position sensor and am planning on installing myself to see if the shops is faulty. Could it potentially be the fuel pump filter? Checked out the air intake tonight and the filter looks brand new.

Pretty much at a loss of what to do and try here, hoping for some guidance.

Thanks for taking the time to read my post.

 

Well because you had a battery issue you might have a security lockout going on. Any blinking lights on the instrument cluster? After you have a good battery, try locking and unlocking the truck three times. If that does not do it you can borrow a fuel pressure tester from oreilly auto parts and test fuel pressure, if you have fuel pressure the problem is likely the CPS again.

 

Has anyone tried to verify anything, like spark or fuel pressure...when it doesn't start or are they just throwing parts at it?

If it's not starting at the moment...check spark. That's the easiest, then check fuel pressure.

Now, since you've replaced a bit of things on it already, and assuming they were installed correctly and decent parts, my next thought would be interior fuse box. Corrosion on the backside, from possible water leaks (windshield), can cause all sorts of intermittent running issues. Pull your kick panel down that covers interior fuse box and look for signs of water, usually, you will see drip marks on the steel tube just above fuse box.

 

I'd be looking at that last fault you listed, the Anti-theft alarm serial link fault, Drive Cycle A. That's the type of thing that would stop one from starting, in my experience with other vehicles anyway.