2004 Blazer No Start

[thirdgenfirescue]

Got a 2004 Chevy Blazer 4-Door with the 4.3. Was driving home one day and it died after i went over some train tracks and will not restart! Put a new rear end and transmission in it just a few weeks ago. Figured it was the fuel pump so I put a new one in without testing anything first (dumb idea!), and it still won't start. Since then, I have discovered it still has no fuel pressure, has no spark, and I can not get our Snap On scanner to communicate with it (works with other vehicles, not an issue with the scanner). It cranks over OK, but I haven't got a chance to test out anything else yet, not sure where to go from here, PCM, ground wires? Any help would be extremely appreciated!

[MT-2500]

Originally Posted by thirdgenfirescue

Got a 2004 Chevy Blazer 4-Door with the 4.3. Was driving home one day and it died after i went over some train tracks and will not restart! Put a new rear end and transmission in it just a few weeks ago. Figured it was the fuel pump so I put a new one in without testing anything first (dumb idea!), and it still won't start. Since then, I have discovered it still has no fuel pressure, has no spark, and I can not get our Snap On scanner to communicate with it (works with other vehicles, not an issue with the scanner). It cranks over OK, but I haven't got a chance to test out anything else yet, not sure where to go from here, PCM, ground wires? Any help would be extremely appreciated!

Get the scanner fired up.
And see if it shows any rpm signal.
You need spark and rpm signal for fuel pump to work.
May be something unpluged.
Check pin 16 for 12 volt battery power.
http://www.troublecodes.net/OBD2/

If no 12 volts on pin 16 start checking fuzes for 12 volts both sides.
Does cirar lighter work?

[thirdgenfirescue]

All fuses under the hood are ok. cigar lighter works, powers the scanner. Thought about the crank sensor, thats what i was trying to check with the scanner.

[MT-2500]

Originally Posted by thirdgenfirescue

All fuses under the hood are ok. cigar lighter works, powers the scanner. Thought about the crank sensor, thats what i was trying to check with the scanner.

You may have more than one fuse box.
Check for proper 12 volts to all fuse and fuse boxes.
Did you test for power and ground on the OBD11 plugin?
What does the scanner say?
Like no communcation?
Are you using just OBD11 on sanner?
What snapon scanner are you using?
Will it read out any transmission or SIR or ABS computers?
Does the check engine light come on key on?