ICM Test?
 

1988 Pickup, 3.0L
Is there any way to test this Ignition Control Module? It's a fairly expensive part for this model and I don't want to replace it unless I'm sure it's bad. Any help much appreciated.

Most part stores can test many different modules. I'm not sure if Toyota modules can be tested at the part stores. They are a rare part to fail. Got any buddies with a 3.0 truck you can plug yours into to check?

Full specs were never published.

The fact you are asking says you probably don't have the tools required for a "proper analysis" even if there were good factory specs given.

Scope did a pretty in-depth write up on these at some point but I don't remember the thread title. If you want to Google for it you may or may not find it interesting..

For a layman's test, if you have healthy sparks it's probably fine. If you want some diy bench tests you can find some on YouTube..

Make sure the mounts/ground are clean and tight and the wires are intact.