Post Reply 
 
Thread Rating:
  • 0 Votes - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
pcm dead?
10-25-2010, 10:17 AM
Post: #1
pcm dead?
My 95 ram 1500 4x4 w/ 5.2L Refuses to start.

I replaced Crancshaft Position Sensor, rotor, cap, Camshaft position sensor, tps, iac....to no avail. The voltage check for the CPS and other sensors fails to show the required 8 volts or 5 volts per my manual. Zero spark.

Coil checks out and is getting 12 volts during cranking. All fuses are good and I have swapped the relays around several times and check for 12 volts as the book says K/on and K/off. Fuel pump is pumping.

Only codes are for the iac and tps which would make sense since they have no voltage or 0.01 volts actually. The only thing I have failed to check is the cpm low voltage output to see if it is a bad wire but I am not sure how to do this and would hate to finish the cpm off with a misplaced probe.

All computer resources has a rebuilt for only (only?) $245.

allcomputerresources.com

anyone dealt with these guys before?

any sugggestions?
Find all posts by this user
Quote this message in a reply
10-25-2010, 01:59 PM
Post: #2
RE: pcm dead?
I chased an electrical problem forever before I realized it was the cpm. I would recommend splurging a little bit more and go to a local parts store that can give you a lifetime warranty. I say this because the first one i bought lasted about a month, maybe 5 starts, before it crapped out. To me if you spend a bit more now with that kind of safety net then it is well worth it. After you get it bring it to your dealer and they can program it with all your truck info as well.

Sorry I don't have any input on how your are diagnosing it. However from what you said that seems to be the logical issue.




1999 Dodge Ram 1500 35" Dynapro Mt's and some other stuff
Find all posts by this user
Quote this message in a reply
10-26-2010, 06:11 AM
Post: #3
RE: pcm dead?
(10-25-2010 01:59 PM)SlimMan Wrote:  I chased an electrical problem forever before I realized it was the cpm. I would recommend splurging a little bit more and go to a local parts store that can give you a lifetime warranty. I say this because the first one i bought lasted about a month, maybe 5 starts, before it crapped out. To me if you spend a bit more now with that kind of safety net then it is well worth it. After you get it bring it to your dealer and they can program it with all your truck info as well.

Sorry I don't have any input on how your are diagnosing it. However from what you said that seems to be the logical issue.
Find all posts by this user
Quote this message in a reply
10-26-2010, 06:15 AM
Post: #4
RE: pcm dead?
Actually, All computer resources provides a lifetime warranty and will input my vin and milage so all I have to do is plug and play.

My real concern is that this will not fix it, just as all my other efforts have failed.

Today I am going to try and determine which wire is supposed to be putting out the reference voltage at the pcm so I can tell if it is a bad wire or the pcn.

I will keep you posted.
Find all posts by this user
Quote this message in a reply
11-01-2010, 03:23 AM
Post: #5
RE: pcm dead?
Refering to my manual I found the supply voltage wire from the PCM to the TPS. It was on the plug closest to the driver (Plug A) pin #7. No surprise as it was the same color (purple and white) as the TPS supply.
My meter showed good continuity. I plugged everything back up and with the key on found only .01 volts there instead of the 5 volts I needed.

So..the pcm is bad. I ordered one from AllcomputerResources.com for 245.00 which includes shipping. Tomorrow will be one week since I ordered and no sign (yet) that they have shipped it.
Find all posts by this user
Quote this message in a reply
Post Reply 


Forum Jump:

[-]
Permissions Box
You cannot Post Threads.
You cannot Post Replies.
You cannot Post Attachments.
You can Edit Your Posts.
HTML is off
MyCode is on
Smilies is on
[img]-code is on
[-]
Permissions Box
You cannot Post Threads.
You cannot Post Replies.
You cannot Post Attachments.
You can Edit Your Posts.
HTML is off
MyCode is on
Smilies is on
[img]-code is on