It started with a no crank, no start. I tried to jumpstart the battery, which made the jump cables melt! When the car turned on the horn started honking in a continuous tone, still no crank. I then swapped out the battery and alternator. Now I have dash lights and electrical working, starter cranks... But I don’t hear the whine of the fuel pump like I usually do. Fuse is good. I still have the OEM pump installed. I was driving fine the day before all this no crank, no start business.

I have an extra ECU with the same exact number (ERR7377) as what’s in my ‘97 Disco. Would I be able to simply swap it out without consequences?
The fuel pump relay I have is between the ECU and the fuse box in the engine bay. Could this be at fault? Would a bad crankshaft sensor also prohibit a fuel pump from engaging?

I have also pressed the inertia switch.

A lot of questions, I just want to know if you guys have had this issue and what you did.


This is the relay I have.

 

If the alarm is going off, its probably the 10AS immobilizing the truck, due to being triggered or the unit failing. Do you have a key fob for the truck? or the EKA code?
You cant just swap ECU's (generally, if it hasnt been modified) as you will need to sync the 10as and the gems ECU.

Do you have a solid red, or flashing red LED at the bottom of the dash?

It is possible for the fuel pump relay to fail, and the starter relay to continue to work. Sometimes that unit can get moisture inside and one or both of the relays can seize.

 

I got a key fob with the truck that doesn’t work, even with a new battery. I don’t notice any red LED on dash. But I can perform the EKA code that I’ve seen in a few videos with turning a key in the door. Unless every disco has a unique code then...

Also, are you saying the starter is also initiated by the fuel relay? If so, I’ll just rule the relay out of this then. Though, I’ll make sure it’s not moisture.

I’m also hearing a little click from the glovebox area when I turn the key.

 

Fob may not be programmed to the 10as, or the 10as is failing which is why its not working.

Each truck has a unique EKA code assigned to the 10as. There is a generic 1515(i think) code that works once or twice.

Starter and Fuel pump relay are both housed inside of that small unit in front of the ECU, if you take the plastic housing off you will see two relays. Here is a screenshot of what a faulty one can look like.



If you can record the clicking, or what the truck is doing, that may be helpful in narrowing down what the issue is.

 

Since you said you don't hear the fuel pump check the electrical connection in the LR wheel well toward the back = fuel pump harness. I'd also lift the carpet and verify the harness is fully seated at the pump and not corroded or burnt out.

 

Curiosity got the best of me and I cut in to my fuel pump relay and removed the chip like some kind of weird popsicle. Everything is spotless, no surge marks.
It’s simply not getting power, I don’t hear a click from it when I turn the key.


And then I found this wire that was dangling from my circuit box. It was dangling on to the frame, and the end was fried. Yikes! Sorry to say, I’ve never known what it’s for. Its connected to some kind of separate 60 amp circuit attached to the frame.


It says “Stinger”. Something for audio?


Don’t know what else to look for, nothing else looks blown or melted. Might as well try a new fuel pump.

 

That is just a fuse and wire setup for an amp that a previous owner probably installed (or maybe another fuse box/etc).

If you're not getting power to that fuel pump relay, then changing the fuel pump isn't going to do anything.
No power to the pump is usually an immobilizer issue if they relay setup is working correctly.

 

I tried the generic 1515 code and nothing changed. Since I don’t know what my personal code is to I don’t know what my options are to disable the immobilizer. But you’re right, Logan, I should get another relay before I get a pump.

 

I found corroded connectors at the inertia switch causing my fuel pump problems, also just to mention, once you turn the key on, the pump only runs for about 15 seconds unless it detects the engine running. fooled me into replacing my fuel pump when it wasn't an issue.

 

Been there done that. Unless you have software to get out of immobilized mode your need to get it to someone who does. Or you can swap a matching 10as and ecu from a donor truck and it should be happy again. I chose that route myself. Not sure if your 97 is advanced evap or not but ideally you want to get an ECU out of a similar EVAP truck. Otherwise the check engine light is going to be an issue. Pretty easy to figure out which is which, the early trucks (96 and maybe some early 97s) have the round charcoal canister. I did send my original 10as box out to england to be repaired by a specialist and it worked but I still had the LED light on and weird issues so I just got a new one and had my buddy with autologic marry it to my truck. I think nanocom can do this too if you have the correct unlock codes (10as and maybe gems). I see sets on ebay on occasion for around 100$. I pulled mine from a junkyard. The 10as box is in the passenger side footwell under the dash next (small green box). There is a work around apparently but I never explored it but PT Schram may be able to help if you can find a way to reach him. He wont post it up because it would be easier to steal your truck.