Hi Guys, was wondering if you guys can help me figure this out? My Disco (2004 SE7 w/237,337 miles) used to run just fine, and now it won't start unless I bypass the starter relay. I went to get gas one day and then it wouldn't start after fill up. First I thought it was the starter so bench test it and it came out okay. Battery is also okay (12.4) so my next thought was to check all the fuses and relay. All the fuses was fine and all the relay was also fine (clicking and no resistance). I also tried switching the relays around for just in case but that also didn't work. I've also replaced my ignition switch hoping that that was the problem, but it wasn't. I'm also not getting any code or codes (except for p420 - leak around my manifold flange to catalytic converter) according to my iCarsoft LRII and Ultraguage so now I'm totally stumped. Seems like my neutral switch is working fine (I'm not getting any code and my M&S lights are not flashing) but I'm not completely certain on that. Starting issue is intermittent. Some days it starts and some day it won't but on the days that it starts on its own, once you turn it off it won't start on its own again. Right now, the only way I can drive the car is by bypassing the relay to start the car and once it's running, there's no problem at all. I've also replaced the fuel pump recently hoping that that was the issue, but to no success. This has lead me to believe that my ECU/BCU are not communicating so I decided to buy the ECU/BCU/Cluster combo hoping that this approach will finally fix my problem. Unfortunately, that still didn't work (I unplugged the battery cables, removed both modules and cluster, installed the new/used ones, attached the cable and leave the key in 2nd position for 20min) After doing the 'transplant" the car still won't start on its own and when I bypass the relay to try to drive the truck around I got the P1668 code. I have switched all of my original modules and cluster on back in my car since the transplant didn't work. Any insight you guys can provide is highly appreciated.

PS. I've also replaced the CPS, Ignition coil, spark plugs and wires on this truck since I bought it almost 3yrs ago and used OEM parts. Also, I don't have my EKA code.

 

Do the correct LCD gear indicators appear in the instrument panel display and do the red LEDs on the shifter bezel light up as you move the shifter through PRND321? For example, does the instrument panel show P when the shifter is in the P position? If not, there's a problem with the neutral safety switch (aka the XYZ switch). Also, try starting the truck with the shifter in the Neutral position. But for that to work N needs to appear in the instrument panel display.

If these checks indicate a problem with the XYZ switch I'd try adjusting it before replacing it.

 

Thanks for the input mln01, and yes, the gear indicator on the cluster matches the shifter bezel as you shift through the gears, and the red LEDs on. I've also tried starting the car in neutral position with the same no crank no start result.
Also thought that maybe the ECM and BCU's communication was interrupted before so I have tried the locking and unlocking with the fob for several times (until I hear the alarm beeps) but the car still won't start.

 

I had the same issue, and even though the lights and displays were all correct it was still the XYZ switch.
Try putting the gearshift into P and hitting the back of it -- towards the front of the truck. The fractional amount of movement used to fix it for me until I cleaned and adjusted the switch on the transmission.

 

Thanks for the advise! I've been out of town and just tried your suggestion this morning. Unfortunately, this trick still didn't resolve my non cracking/starting issue. I tried hitting the back of the gearshift several times, but no dice. Every gear looked and felt like it's engaging fine and in synch with my cluster display. Brand new part is quite pricey to just replace it without definitive symptoms to be the actual problem.

What do you guys think? I can really use everyone's input on this non crank/start issue. Open to any or other suggestions.

 

Did you clean/adjust the XYZ yet?

 

More than likely it's the crankshaft position sensor they tend to go bad intermittently especially when hot

 

Nothing about this says CKPS. That would stop it running completely.

 

My weekend got away from me for being out of town last week but this is next on my list (clean XYZ). I appreciate your suggestion!

 

CPS was recently replaced with brand new part, and it didn't fixed the issue.