Hi all. Some direction please: I have had a North American ’96 LR Discovery 1 4.0L for two years now. It does NOT have a spider box and I have all the manuals. It is now stranded in New Mexico on BLM land (not four-wheeling, it's just coincidence.) It turns over but will not start. Some of the time, it won't turn over until the second or third try. I have read dozens, if not hundreds of threads about the no-start problem, immobilizer lockout, etc. So many of them don't have absolute solutions. I’ve dealt with this before and then it would miraculously fix itself after various fiddling with no seeming correlation to anything. Sometimes it fixed itself with no fiddling at all. This time it just won’t go.

Things I have confirmed:

Multi-function relay works.
I have 12V to the ECU and 5 volts coming out of various pins for sensors.
Fuel pump runs and I have good pressure on the rail.
12V to the ignition coils.
A new MAF was installed last fall.
New Idle air valve last fall
New TPS last fall
New fuel pump last fall.
OBD will NOT connect to my unit (I use it regularly on this vehicle.)
Inertia switch closed.
Ignition switch seems to work positively using a voltmeter to check continuity.


I DO NOT have a PIP (FOB, whatever.) Never had one. I removed the door lock actuators a while back because I was sick of being locked out for no reason..and I don’t care if the vehicle locks. In fact, I don’t care if much of anything works except that it RUN.

I will replace the Crankshaft Position Sensor and shield when the parts come in. I know that is a common failure. It was feeling loose and now it must be replaced because I bogeyed up the shield trying to remove it.

Questions:
Is there any way of KNOWING that the immobilizer is in effect?
ECU dead? (I might have accidentally plugged it in with the ignition on.)
Will the immobilizer keep the ECU from talking over the OBD connector?
Recommend bypassing the immobilizer per the threads about which pins to jumper?
Are we positive it HAS an immobilizer? (Look behind the glove box, correct?)
Suggest I get an ECU/alarm set for the next diagnostics trip?
Any suggestions on what else to check on my next trip out to the middle of nowhere?

I'm an engineer, good with a meter and a soldering iron, and not afraid to tear things apart. I can usually fix things as long as I fully know how it works. That's the trouble here - it is remarkably complicated for what it is.

Thanks in advance.

 

The only way to bypass the immobilizer is to contact Tornado Systems | Engine Management Technology Specialists, he can flash a new (recycled) ecu and it removes the immobilizer part. No more no starts, I have looked every where and even looked at the schematic of the system. The immobilizer sends a signal to the ecu to confirm starting or not starting. no matter what wires you remove, eliminate, ground, it will not stop this. Tornado systems quoted me 500.00 plus postage to usa. I'm sorry to tell you this, I have looked for 2.5 years for a different solution, and my brother has his PHD in electrical engineering. Good luck, I plan on the tornado ecu for my disco 1, its half price of one tow bill.

 

Thanks for that. Good to know. Is it possible to get a matched ECU and Alarm set and have it plug and play?

 

yes, if they come from the same truck you can install them in yours

 

There is a guy on this forum that sells them guaranteed to work. I'll try to find his name and info.

 

There is a post that tells you which wire to cut and join to bypass the immoboliser, didn't work for my TDI disco but may work for you.

 

I have a D1, but my son's P38 had a mystery no start which after a month of testing and trying everything imaginable with an ecu/alarm system malfunction looking like the only answer, well turned out it was the cps. No code, no reason to suspect, the truck had started and run normally the night before it didn't. Point being chage that part before jumping to the ecu.