The ignition switch controls power to a lot of systems in the truck. If you need help diagnosing your problems, you really should post your question in the appropriate technical section. This section is for the discussion of the presented material in terms of additions, corrections, or omissions that may be necessary to make the article more complete.

 

I hope I'm not bothering this by bumping, but its related.

I believe it was over a year ago I had the same symptoms as already mentioned. Instead of replacing the switch I elected to take it apart and clean the contacts. Just a couple days ago I experienced the same no start/security light issue again. This time I purchased a brand new one and installed it.
When I took the old switch apart last year, for the life of me I could not get that big return spring to go back in, so I ended up with a springless switch. But today, I was able to get it back in. I also noticed, you do not have to take the entire switch apart to clean the contacts.

Aside from already being mentioned about installing relays to reduce the amount of amperage going through the switch, I really see no other alternative to reducing the load on the contacts.

Frankly, cleaning the contacts can be done while still in the vehicle. The steering column housing still needs to be removed, and you just need to remove the switch from the column. Just be sure to disconnect your battery.

 

No problem with the bump! It's always good to have more discussion on topics like this.

One of the problems with cleaning the contacts is that often the surface is left rough which will tarnish more quickly than a nicely polished surface. If you are going to clean them, I would put a dab of dielectric grease on each of them to give some additional protection.

As far as a relay setup, it wouldn't be too terribly difficult. You really only have to do those contacts that have high current draw going through them. You would need to meet or exceed the amperage of the fuse for each of the inputs to ensure safe, reliable operation on each of the outputs. I believe that this could be accomplished with 3 50A relays on IGN0, IGN1, & IGN3. You could add another for the ACC output and a 30A relay for CRANK output which would capture all of the contacts that are used in these switches. That would create a low amperage connection at the switch saving the contacts.

One thing that this wouldn't address though is the issue of the passlock sensor going bad which is almost as prevalent as the contacts going bad.

 

Where is this Ignition Switch located, anyways? I have a '98 Blazer, my Repair Manual stinks!!! It often uses different names and terminology, for things, than are normally used by people in real life.
I had replaced the Electric Coil ($44), Ignition Control Module ($83), and the Starter Motor & Solenoid ($124), in February 2011. I did all this to get the dang thing to start and run. This may have been when I had Codes P0780 and P1860 come up before, but I'm not sure right now, still reviewing my Notes and Maintenance File.
OK.. I found a Note, that says 12/7/10 Service Engine Soon Light came on. Codes P0740 and P1860. So it could have taken 2 months for blazer to NOT start and run, before I did anything to fix it.
New FREE Fuel Pump was put in on 1/30/11.
New Sears Diehard Battery on 7/19/09, so it is 2 years & 2 months old.
Had had trouble with 4WD, but y'all helped with that. I took out the 4WD Module for awhile, then put it back in. Then the 4WD worked fine all Winter. That was on 12/19/10.

 

I KNOW I've seen a how-to for removing and installing the switch but I can't seem to find it this morning. Does anyone know where to find or feel helpful enough to post a link here? Thanks a ton! I've got a switch on order for this afternoon and want to remove the old one to get a head start on the operation.

Thanks in advance!

 

Found the How-To Install Ignition Switch forum:

https://blazerforum.com/forum/articl...-thread-26553/

 

So what is the part that I need to buy in order to fix the problem? I replaced the Ignition Lock Cylinder, but I am still having then issue of the dash lights and fuel pump not coming on all the time when I turn the key. The starter works every time no problem though.

 

Ignition switch is what you need to purchase...

Durlast LS1076 is the only one Autozone carries.

But don't throw out the old one. Keep it. You can gently clean all the contacts and put the old switch in a drawer for future use. When the new one starts to do the same thing, put the old one back in. Works for me anyway.

 

I've also had the 0300 code recently on my 2001 Jimmy SLE with rough idle and engine shutting down. Started as a blip here and there now it's not drivable due to shutting down and running like crap. Along with that I can't find whats poppong my IGN "E" fuse under the hood at start up.

Done the normal stuff. Dist cap, button egr valve etc. Getting ready to replace the coil and ign module.

Any one think that the fuse blowing and the shutting down could be related to the ign switch?

PS. Anyone have a good source for wiring diagrams or prints?

 

I have been working on a circuit design to integrate a marine grade, 120A, normally open, heavy duty relay to bypass the IGN 1 contact. These marine grade, high current relays have threaded studs on the high current side and are a steal at $10-$15 bucks apiece. When I get my mods done and complete my split charging circuit for my trailer, I will upload everything, but it will take me a bit of time yet.