I have determined my 0443 is a result of a short. Replaced some bad valves and rotten hoses after smoke test. I have no juice to two fuses in the panel drivers side compartment. Both are GEM related. Have power to engine fuses. So it seems to me the short lies from the engine compartment to the cabin. I'm looking for a diagram of the harnesses going to the gem and fuse box so I can test each wire. Think I just answered my own question. I am getting four 0443 codes. One confirmed and three pending. Stupid question but does this indicate four separate issues? Thanks folks. This forum has helped a great deal getting my truck operational again. Just this code that is holding me up.

 

Are we supposed to guess what you're working on?

Are we supposed to guess WHICH fuses, valves, and hoses you've worked on or have issues with?

If all you need is a diagram, your best bet is to buy a service DVD or CD off eBay, then you have a complete set for whatever you're working on.

 

Well i'm sorry for that. It's a 97 F150 4x4 with a 4.2.

Replaced some of the vapor hose from the purge valve back.
Replaced the charcoal valve that was bad in the rear for the tank vapors.
Replaced the GVR(?) valve as it was bad.

Like I said, I did a smoke test and found a leak in the engine compartment passenger side and fixed that. No more leaks anywhere that I can see.

The bad fuses are #15 and #20 in the fuse panel cabin drivers side.

I have tested all the valves within the emissions circuit system and all check out OK per the forums suggestions and information. So from that I started checking the electrical as suggested and because it all sounds like a short somewhere. Not knowing anything about anything electrical in autos I checked the fuses with a light meter. Got the results mentioned before. Because of the water issues with the year truck I swapped out the fuse box. it corrected some of the other bad connections but still left me with the 15 and 20 as not getting juice.

I figure I can check each wire from the main fuse box in the engine, through the fire wall to the GEM and interior fuse panel. The interior drivers side grounds to the chassis are good. It's such a rats nest with that harness.

I was looking for the color codes or descriptions of the wires so I could go straight to the GEM wires that are probably bad instead of testing each and every wire in the harness if that is possible.

Again, the forum has helped me a great deal to this point and thanks to all those that contribute. Joe-another rookie (mistake)

 

CJB fuse F20 is HOT IN START only and comes from the ignition switch and starter relay. You have to check it for power when the key is in START.

Fuse F15 provides keep-alive power to the GEM and should be "ALWAYS HOT". If CJB fuses F13 & F14 are ALWAYS HOT but F15 is not, there is an open circuit in the CJB. Did you pull F15 out and inspect the prongs that hold the fuse in there to see if they're damaged or stretched?

Neither is associated with the P0443 which is for an electrical circuit fault for the CANP valve.

 

I did check F15 and it crackled when I put back in which started this electrical chain of events. Thank you by the way for your reply. cJB=? Cabin junction box?sorry but where is it located? I will check into it tomorrow. I replaced fuse box so I am assuming there is no short but will look further. I was leaning towards a short that speaks to or from the PCM. That is where I am at unless there is cracked hose I may have missed. Thanks again.

 

CJB= Central Junction Box - the fuse box under the dash.

Your only reported fault is the P0443 which I already explained is an electrical fault with the purge valve. You've not reported any other material symptoms, so, if you have any, better get to it.

 

Nope. Just the 0443. It test ok for volts and ohms.

 

Test the CIRCUIT! That is what the fault code is telling you.

 

As I said I know nothing about electrical. So my next question would be how to test the circuit. I tested the power to and get 12V and the ground is within range, can;t remember the actual reading. Where do I go from here?

 

You need someone who knows how to do electrical troubleshooting.

 

Back to square one. Thanks for your fuse input