98 Jimmy No Spark No Fuel No Start Security

[Bosco11]

I have a 98 Jimmy that has been sitting a while. I have been driving it about once a month for around 6 months to keep everything going. Around Thanksgiving, I jump started the truck, and took it for a drive. At that time, I noticed that I could not get the key into the lock position, and therefore could not remove the key after shutting it off. Additionally, my fuel gauge, temperature gauge, and speedometer were not working, even though the vehicle was running very well.

I shut the vehicle off, and started looking for blown fuses. I ended up finding that the cluster fuse on the left side of the dash was blown. I replaced the fuse, and it blew immediately.

Since the fuse immediately blew, I decided to start the vehicel and replace the fuse while it was running. After I replaced the fuse, the fuel gauge and temp gauge came on. And then the vehicle died. I noticed that the security light came on. And since then, the security light has remained solidly on.

I checked the passlock wire coming out of the ignition switch, and measured 3.2 k ohms when the switch was in the start (cranking) position.

I have removed fuses, disconnected battery for days at a time, and I cannot get this vehicle to start.

The fuel pump, which was replaced a few months ago, is shut down, and there is no spark. I shorted the contacts of the fuel pump relay and the fuel pump does run when I do that.

Right now, it cranks and cranks, with no fire or fuel.

After I have reconnected the battery, the security light is off. But after I crank it, the security light comes on, and stays on. It even stays on after the key is removed.

[MT-2500]

Try the reset procedure.
Key on 11 minutes off 1 minute and on for 11 minutes off for 1 minute and on for 11 minutes. then off 1 minute and then see if it will start.

P. S. use jumper or battery charger when doing this.

[Bosco11]

I blew fuse number 11, on the left side of the dash. This fuse feeds the instrument cluster as well as the ecm. My best guess of how I blew the fuse, is by jumping the vehicle with a high current charger.

After much trial and error, I have determined that the ecm is definitely shot.

I am ordering a new ECM from ebay, which will come programmed with my VIN information.

I'll update this thread whenever I get the truck running.

[Bosco11]

Problem solved.

I ordered a used ECM from a guy who programs them, therefore, I did not have to go to the dealership.

I installed the ECM, did the relearn procedure, and the vehicle is currently running like a top.

I guess the moral of the story is to ensure your ECM is operating properly before going down the "security problem" road. I think a good indication of the ECM actually doing something is when the "Service Engine" light is on.

Thanks for your help.