2003 Blazer 4D 4x4.
When I turn the key the fuel pump will engage or not on a random basis. I had it towed to a garage and they ran all the standard pressure tests and found everything working properly. ( Forgot to ask what they did to get it running again). They did tell me that they also swapped the Horn/Fuel pump relay. I was told by them that there is nothing else they can do until it happens again.
I keep seeing in the posts a reference to the igniton Control Module as a possible problem.
1.Is there a way to check to see if this is the problem? (Short of replacement)
2.If I need to replace it where is it located and can it be done by a novice?
Thanks.

 

The ICM will not cause the fuel pump to not turn on.

You can remove it and have it tested at a number of autoparts stores. It is located on the same bracket as the coil on top of the engine towards the passenger side and near the distributor. While you are at it, have both the ICM and coil tested.

But again, if your fuel pump is not coming on for whatever reason, the ICM is not the source of that issue.