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Discussion Starter #1
i just replaced my cps with a brand new one, still no start and still no tach signal... i'm stumped on this one? any help?
 

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new one is dead. Also check the wires.
 

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check fuse 22 and fuse 9
 

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Discussion Starter #4
i've checked both of those fuses underhood, both are fine, still test ok for continuity.
 

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Discussion Starter #6
grrr.... i'm getting sick of swapping cps's, especially at $90 a pop. the pcm is accessible through the driver's fender liner, right? anybody got some spares i could try? i'll pay for shipping and buy ya a beer!
 

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[ QUOTE ]
grrr.... i'm getting sick of swapping cps's, especially at $90 a pop. the pcm is accessible through the driver's fender liner, right? anybody got some spares i could try? i'll pay for shipping and buy ya a beer!

[/ QUOTE ]Look in the HPOR , oil needs to be 1/2 " from the top. How old are the batts ,Is it spinning over fast enough. where did you get the CPS that is in there now ?What happened to cause you to change the CPS in the first place?....
 

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Discussion Starter #8
truck cranks just fine, i have no tach movement during cranking, leading me to think it was a cps issue. hpop oil level is fine and shouldn't affect the tach signal.
 

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hpop oil level is fine and shouldn't affect the tach signal.

[/ QUOTE ] Did you look..? I know it won't effect the tach, the reason I asked , is ,If you have been cranking it for a long time , the resevoir may be low...
 

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is your WTS lighting comming on when you turn the key on. I'd check for blow fuses.
 

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Discussion Starter #11
oil level is fine, and wts light is working properly. is there anything other than a cps that can cause no tach signal?

if it is the pcm, how can i test for that? besides swapping one in?
 

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I'm all ears on this one, too.

No start, no tach, CPS was less than a year old, but I swapped for a new one anyway. Still not tach or swap. fuses ok.
 

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I'm all ears on this one, too.

No start, no tach, CPS was less than a year old, but I swapped for a new one anyway. Still not tach or swap. fuses ok.

[/ QUOTE ]Triple check the fuses #22 & #9....
 

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They've been triple checked. Is the next troubleshooting step putting in a new PCM?
 

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[ QUOTE ]
They've been triple checked. Is the next troubleshooting step putting in a new PCM?

[/ QUOTE ]Tell us how you got to this point...What started this ?....
 

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I'm just a bandwagoner of the thread. It was started by fastg60. I'll let him chime in because it's probably different than mine.

Matthew
 

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I'm just a bandwagoner of the thread. It was started by fastg60. I'll let him chime in because it's probably different than mine.

Matthew

[/ QUOTE ] Matt ,thats why I asked you... . Yours may be a different problem
 

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Dang, things always change.

I got here by having a truck that wouldn't shut off. I could take the key out and everything.

EXCEPT, I could get it to shut off if I put it into 4WD. So I just ended up using my transfer case selector as my "off" switch until I could track down what was backfeeding the PCM. Still haven't found it.

fast forward a few months, lots of cold temps, burned up my starter when I forgot to plug in a few mornings. Found out batteries, though young, were dead, free replacements at walmart.

New batteries in, now it won't even turn over. check cables, etc. Find loose wire on starter, but it won't tighten up, the stud just keeps coming out and keeping the lug loose. New starter at Advance Auto (free because I had bought the "lifetime" warranty a year ago.

Then it starts. I can finally get sheet goods from the hardware store that I couldn't get into a minivan.

Fast forward a week, truck is dead. I notice there is no tack reading during the cranking. I've been through one bad CPS before, so I buy a new one and install it. No dice. No starting, no tach reading during cranking. Pulled chip, etc. nothing changes. take out 10k mod, nothing.

Check #22 and #9 several times. nothing.

mess with CPS wires and pull ICP. nothing.

check HPOP, full. still not starting.

Put it into 4wd, nothing.

Charging batteries by this time.

That brings us to today. I try it again, and everything works!

Cranks, starts, the whole thing.


AND I have my first ever CEL!

Almost a badge of honor. Hope that Advance's scanner can read it. Also hope it's not some trivial code.

Not out of the woods yet, we'll see what the next few days bring.

Any ideas?
 

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WOW...have you checked out the actual ignition switch. Not the key one , but the one that the key activates? Isn't there a small relay that powers the PCM in the distribution box under the hood?....
 

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didn't know about another relay, that would be interesting news. Very welcome, interesting news. Doesn't solve my 4WD selector issue though. I'd love to hear more about this extra relay. Is it in the column?
 
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