Hi my name is Brian, Have just bought a 1989 full size blazer. i live in Kuwait and work so there is not much help here.

MY blazer dose not start battery is good. Nothing happens when turn the key. use some help.

 

No clicking from the starter motor?

Nothing at all?

Let's start from the beginning:

You say new battery - Do the interior lights go on when you open the door? (Some batteries have spyglass and a green or red dot according to their charging status - is it green?

When you turn the key to ACC - Does the dashboard come to life and show the usual warning lights? (ABS, oil pressure, voltmeter)

When you turn the key further to the START - What exactly happens?
- Do the lights go dim?
- Do the dashboard indications go dim?
- Do you have a clicking sound from the front? (Once per key turn or like a rattle - if it rattles most of the time also the lights go dim)

Things you can do in the meantime:
- Do yo have the user manual?
- Locate the fuses and check on them - all of them

 

No clicking, checked the fuses, Dose nothing when i turn the key. no lights on the dash. when i turn the head lights on there strong the battery has 12.6 charge. thank you for the help.

This is a 1989 k5 blazer with 5.7

 

sounds like possible bad ignition switch. Do you have one that you could swap out to check it?

 

Would most probably need a wiring diagram.
As GB2002 suggests to start at the key. With the diagram one could figure which relay is starting up all the electrical and which wires should be "always hot" to the lock.

As I understand your headlights work. So this part seems o.k. and it affects all the "on-key" services.