the Remote keyless programming DIY said if you have RPO Code AU0 you have RKE.. well, I don't have AU0, BUT I *DO* have this:
AX3: Lock Control, Keyless Entry System so does my '94 s10 have RKE? (I don't have fobs, the guy I bought it from never got any either)

 

I'm trying to remember when those cars with chips in the keys came out, those cheap"anti theft" systems they had for a while. My dad had that in his dodge stratus...

 

It doesn't have PassKey if that's what you mean. It uses the old school square IGN key

 

Hmmm... not too sure then. Might be a bit for this one... hopefully someone chimes in soon, but 1st gens are a small ground of knowledge unfortunately...

 

I'm no expert on the keyless entry systems but my 94 S10 Blazer has factory keyless entry, and came with one OE fob.

It uses this fob: https://amzn.to/2xSThTH The notes on it say "KEYLESS ENTRY SYS LK(AX3)" so it sounds like this is what you need. If that's listed in the RPO codes the receiver module should be in there already.

I know these were the standard GM keyless systems in the early 90s. The rounded remotes (these: https://amzn.to/2W1I3nU). . .which I believe is the RKE system you're referring to didn't start until the 2nd generation S10's. If you've got a 94 S10 then there may be some weird cross over stuff being the 1st year of the 2nd Gens. If you've got a 94 S10 Blazer like me, then the first link should be it.

edit - I just went out and confirmed I do have the same RPO code as you. . .AX3

 

Thanks for the info!!!!
That was what I needed to know.

 

You're Welcome. Glad it was helpful.