So riding home today, the truck briefly hick-up'd, dash lights came on and gauges went dead for a second, (like it has been doing, I was suspecting a CPS) except this time the engine did NOT cut out. It just hick-up'd and kept going. Except the CEL came on...and stayed on. First time this has happened since I got the truck.

So after charging the laptop...

I checked for codes. NO p-codes. The ones I DID have were all "Hybrid Electronic Cluster" codes.... GEM codes. :doh:

U1059 - SCP (J-1850) Invalid or Missing Data for Transmission/Transaxle/PRNDL

C1284 - Oil Pressure Switch Failure

U1027 - SCP (J-1850) Invalid or Missing Data for Engine RPM

U1262 - SCP (J-1850) Communication Bus Fault

B1352 - Ignition Key-In Circuit Failure

 

Possibly the wires going to the gearshift leaver rubbing. I know that will kill power to the gauges and pedal. Usually it blows a fuse though. Might be something to check out. IIRC on the 02 it's fuse 45.

 

I haven't blown any fuses...and I don't believe there's any way that would pop a CEL.

At this point I will be swapping my CPSs out and see if that effects anything.

 

I have not had either failure on my truck. CPS would be a good start. Which one are you running?

 

At this point I have a NOS Black CPS... It has been in since November 2011. I have the Grey "Recall" CPS in the glove box and will be reinstalling that before I drive the truck again, hopefully that's all it is.

 

What does NOS stand for?

 

New Old Stock. I would have said NIB... but there was no box.

 

I guess you got it from Clay or Bob or just didn't do the recall? I have one that I will let go for a small fortune.

 

I actually got it, and a grey one both NOS for $30. Sold the grey one (since I had one) It's only been used for 6 months tho. Kinda expected it to go eventually, but I was hoping to get a year or two out of it. The truck really does (or did) run better with it.

 

Ok, so update time:

I changed the CPS on Wednesday from the black one to the recall/grey one.... drove fine for a couple days until this morning....and once again driving the engine just shut off. I slap it into neutral, it won't re-start. I quickly (while rolling at 50mph) turn the key off/on and it starts back up like normal.

This is just a really weird issue. I'm going to start with checking the main harnesses as best I can for any issues. (Fraying/cuts.) I will also check the grounds that I can find....

Does anyone have a list of all the ground locations?

I'm debating removing the chip as well just to rule that out.

Any other ideas?

 

I've seen the communications fault before. It just lit the idiot light. It didn't kill the engine or anything else.

When you say the dash lights come on, you mean like when you first turn the key to run and wait for the glow plugs? Did the glow plug light come on too? You may want to check out your ignition switch.

 

When the lights come on...yes. This morning however no lights came on...it just died. It is very inconsistent. I have had it die under hard acceleration.... cruising, hills, flat, wet, dry. Short of it won't re-start until after I shut the ignition off/on I can't find any consistencies.

What would I be looking for in the ignition?

 

I uploaded a wiring diagram. Click on my user name in this post, then view public profile. On the right side there is an album with the diagram in it.

Turn the ignition to position 2 (run). There should be 12v coming from the central junction box and 12v out (please ignore the coil on plug on the diagram, I could only find the one for the gas truck). Find the 12v output and monitor it while you shake and rattle the column. See if you can cause it to drop out. Work the key without rolling the switch also.

Check the 12v in the same way, and look for rub marks on the wires and burn marks on the connectors. A burnt pin in a connector will cause strange things to happen.

 

When my chip was first put in my truck did this. Reseated the chip and all has been fine.

 

So.... 350 miles later...

I officially diagnose it as being the chip/connection issue.

For now, I will try to contact PHP tomorrow, and in the mean time start the process of pulling the engine.

Not happy about that.