No crank no start 98 Chevy k2500 5.7 vortex (Solved)

[Feral peasant]

Greetings & welcome to the GMT400 forum!

In order to get a better feel for whatever ails your K2500, if you could
take a moment and share a brief history of how this truck has functioned?

* Has it ever worked for you, or did you buy it for the right place because it didn't start?
* If it used to work, but quit, how long has it been sitting? How strong is the battery? Fully charged?
* Was it running perfectly & suddenly stopped? Or did it grow more intermittent over time, until it finally stopped responding at all?
* Theft recovery? Recent Accident?

You get the picture. Those of us who try to troubleshoot remotely need as many clues as
you can give us to work with.

****

Alright, a No Crank/No Start situation is normally something straightforward, fixed with a fresh battery,
starter swap, or the tightening of a electrical connector. But if all this have already been double-checked,
let's dig a little deeper.

How about we first identify what specific fuses are involved, and have you check those first? And
if we don't find anything there, then split your engine cranking circuit near the middle, in order to try and figure
out which direction (upstream or downstream) we need to go?

Here's the start circuit wiring diagram for your '98, control side first:

You must be registered for see images attach

NOTE: Fuse 6 (IGN A) is located in the "Underhood Fuse Block", whereas Fuse 8 (CRANK) is located in the Instrument Panel fuse block. You need *both*.
If either one is blown, then no joy. Replace, retry. If it now works, why did the fuse originally blow? On the other hand, if it blows again,
then we need to identify what's causing the excessive current draw.

****

To help you navigate the Underhood Fuse Block, I've attached 3 pics: 1 bird's eye view, followed by a look at the legend on
underside of the dust cover, and finally how the relay sockets are laid out, comparing wiring diagram numbering scheme to physical implementation.

Note that in this photo I'm actually showing you the Fuel Pump Relay socket, but since all 3 relays on the lefthand side are identical and
the plug orientations match, if you follow the legend and pull the starter relay (upper Left corner in the photo) you should be good to go.

*CAUTION*

The next step involves jumpering 12v power. Unless you are completely confident, capable, and comfortable doing this,
STOP here & take this to a qualified mechanic and let them troubleshoot this.

OK, you still want to proceed? Before going any further, if the truck is an Automatic, it must be in either Park or Neutral.

Parking brake set. Wheels safety chocked. Or enlist a helper with a foot firmly on the brake pedal. And if it is a standard,
it MUST be in neutral. Why all the precautions?

A: Because for troubleshooting purposes we are temporarily jumpering around the Clutch Safety / Neutral Safety Switches,
and if the precautions above are not honored, the engine could turn over, start, truck takes off, folks get hurt, news at 11. (!)

Still here? Alright, one more wiring diagram to look at so that you understand what I am asking you to jumper: (Starter Relay socket, Pin 30 to Pin 87)

You must be registered for see images attach

Looking at the schematic, if we were to take a wire and jumper Pin 30 to Pin 87, this will apply
Power from Fuse #6 directly to the Starter Solenoid. IF this gets the engine cranking, then we
now know that we have a Control issue:

* Starter Relay bad, or
* something upstream in the control chain, possibly all the way back to the Ignition Switch.

On the other hand, if the starter *still does not crank*, then obviously head down to the starter.
And as @xXxPARAGONxXx stated, fix the grounds. No broken grounds allowed anywhere in the
GMT400 engine bay.

Actually, it could be argued that you should try to fix any obvious wiring issues *before* trying
the diagnostic step I outlined above.

****

Enough for now, I'll stop here and await a status report from you before going any further. If you
have any questions don't hesitate to ask. And sometimes a photo to go along with the question
is invaluable/saves time.

Let us know what you discover.

Good luck --

I tried some different fuses I pulled from pick an pull, nothing got the battery recharged I think it made a sound trying to activate but I couldn't really hear because my heat is stuck on, there only 2 wires I could think of (one wire connects the frame to the cab)(the one wire that snapped that connected to the engine block{but it started fine and ran fine without it}) I replaced the starter as well I'm having my friend look over the wiring diagram since I have no idea how to read any of it

 

[Road Trip]

I tried some different fuses I pulled from pick an pull, nothing got the battery recharged I think it made a sound trying to activate but I couldn't really hear because my heat is stuck on, there only 2 wires I could think of (one wire connects the frame to the cab)(the one wire that snapped that connected to the engine block{but it started fine and ran fine without it}) I replaced the starter as well I'm having my friend look over the wiring diagram since I have no idea how to read any of it

Appreciate your candid status update. If your friend has any questions after reviewing
the wiring diagrams I'd be happy to try and answer them. We all started where you are,
and if you are willing to learn more about your K2500 then I'll share whatever I can over
this screen.

For what it's worth, I have more respect for someone new to all this but is willing to learn,
than someone who's done this their entire career, stopped learning at some point, and
isn't interested to add anything new to their skill set.

****

Q: Have you ever heard this truck run? It's OK if you haven't, just trying to figure
out just how good/bad your electrical harness is.

 

[Feral peasant]

Welcome to the forum from Oregon.

You have loaded and fired the parts cannon with no luck. Address the obvious ground strap, even if it does not fix this problem. A no crank condition will not be fixed by a cap, rotor or coil. Does the engine crank if you cross at the starter solenoid? Mr. @Road Trip is giving you great info. Likely gonna find a component in the crank circuit. One other thing that may have been asked already, any recent w

Appreciate your candid status update. If your friend has any questions after reviewing
the wiring diagrams I'd be happy to try and answer them. We all started where you are,
and if you are willing to learn more about your K2500 then I'll share whatever I can over
this screen.

For what it's worth, I have more respect for someone new to all this but is willing to learn,
than someone who's done this their entire career, stopped learning at some point, and
isn't interested to add anything new to their skill set.

****

Q: Have you ever heard this truck run? It's OK if you haven't, just trying to figure
out just how good/bad your electrical harness is.

Yeah no I'd live to learn about this, I started getting into it when I bought the truck a year ago. Yes I have heard it run I drove it until recent when this problem started. Only electrical work I've done is installing an amp and subwoofer, worked fine after install (7+ months ago) before Ive done all this work the triple A guy was able to start it by just hitting the solenoid mounted on the starter

 

[Road Trip]

Yeah no I'd live to learn about this, I started getting into it when I bought the truck a year ago. Yes I have heard it run I drove it until recent when this problem started. Only electrical work I've done is installing an amp and subwoofer, worked fine after install (7+ months ago) before Ive done all this work the triple A guy was able to start it by just hitting the solenoid mounted on the starter

That's a relief. It's not you, it's just that sometimes folks show up to this
forum with a 'new to everyone' vehicle, ask for help getting it started...and only
after several tries to figure out what's wrong the new owner happens to mention
that they just dragged the truck out of a field where it's been sitting for umpteen
years.

The fact that you've actually seen/heard it run in recent memory is a good thing.
If we can put the wiring back to a 'known good' configuration then we can
reason through whatever symptoms subsequently crop up.

****

So listen, while you are waiting for your buddy to review the start circuit
diagrams, you should download the full set of '98 Factory Service Manuals.
This way you can start doing a little research on issues as they come up.

Here's the link to follow: (Factory Service Manuals)

And be sure to check out all the GMT400 stuff going on in here. It's
a really good forum, full of good people.

Cheers --

 

[GoToGuy]

With all that butchered wire and insanity. If you've gotten the OE service manuals , there are good views if how it's supposed to look. Yeah, wire diagrams were a challenge for everyone, there are utube vids to explain schematics, watch a few.. The service manual written on level for Joe average, not rocket scientist. Everybody starts at zero.

 

[Feral peasant]

That's a relief. It's not you, it's just that sometimes folks show up to this
forum with a 'new to everyone' vehicle, ask for help getting it started...and only
after several tries to figure out what's wrong the new owner happens to mention
that they just dragged the truck out of a field where it's been sitting for umpteen
years.

The fact that you've actually seen/heard it run in recent memory is a good thing.
If we can put the wiring back to a 'known good' configuration then we can
reason through whatever symptoms subsequently crop up.

****

So listen, while you are waiting for your buddy to review the start circuit
diagrams, you should download the full set of '98 Factory Service Manuals.
This way you can start doing a little research on issues as they come up.

Here's the link to follow: (Factory Service Manuals)

And be sure to check out all the GMT400 stuff going on in here. It's
a really good forum, full of good people.

Cheers --

I appreciate the help I was able to get a tester and found out my ignition wire was clipped in the middle had to re run it and it worked

 

[Road Trip]

I appreciate the help I was able to get a tester and found out my ignition wire was clipped in the middle had to re run it and it worked

Thanks for coming back and sharing your solution! It would be nice if more
people asking for assistance followed your lead & closed the loop like this.

NOTE: On a unmodified wiring harness your reply would translate to the PPL (purple) wire
between the starter relay and the starter solenoid was 'clipped in the middle', thereby
losing the human-initiated 'control signal' to the starter itself.

Enjoy your '98 K2500 with the upgraded sound system. :0)

Congrats on the fix. Cheers --

 

[movietvet]

I appreciate the help I was able to get a tester and found out my ignition wire was clipped in the middle had to re run it and it worked

You can go back to your original post, #1, and at the top right of that post window there is 3 dots. Click on there and you can edit the original thread title and include the word "SOLVED" and then whoever is doing a search will see that and read the whole thread.