My truck recently started throwing up the 0403 code. Double checked my SG2 by clearing it and it shows 4 codes all 0403. Pulled the Egr and it had a fair amount of dry soot on it so I cleaned it and tried again. 0403 still shows up
What is causing multiple (4) 0403 codes. When I cycle thru the code numbers for a brief second it will read 0405 before instantly switching to 0403.
Oil and water temps mirror each other with a few degrees of separation when the trucks been on the road for a while. What am I missing to clear this code or is there something more I need to look into

 

You either have a faulty valve or circuit. 0403 and 0405 are both circuit "A" codes.

 

How would I fix the circuit problem I do know anything about tracking that down.

 

Broken and/or wires that are chafing.
A bad plug can also be a problem.
Time to start chasing wires. Look at each
wire and the harness that it comes from.
clear damage is the easy one. It's the hidden
stuff that will drive you crazy. Feel the wire for
crispy or spongy spots and check there.


Sean

 

Its an electrical Problem with the EGR Valve or EGR Electrical Circuit

Have A DVM??

 

Ok I'm following you now with the circuit , does the egr itself fail or is this just an electrical / plug issue.

 

Most common I believe would be the EGR Valve itself failing

Affter that would be wire Harness

P0403 EGR Exhaust Gas Recirculation Control Circuit Open circuit, short to ground or voltage, EGR valve


You can take the DVM and Back Probe the EGR Valve Plug

Here is A WIre diagram
https://www.ford-trucks.com/ford-man...%20diagram.pdf



Check for the following with engine Running

Vehicle Power 12 volts @ PIN#E
V-REF 5 Volts @ PIN# D
Signal Circuit @ PIN# C
Ground Circuit @ PIN#B
Signal Circuit @ PIN# A

If it don't have all the Circuits working correctly we can get you the PCM Pinout to chase it that way

 

Thanks very much that will really help

 

p0405 is more then often a valve

 

So I replaced the EgR no luck ,metered the plug and and found the following values
Red- 16.6
Brown- 6.0
Grey w/ orange stripe 0
Grey w/red stripe .06
White .01
What should I do next I'm surprised by the first value since its supposed to be 12 but what does it mean and what should I do next

 

IPR how did we get to that I thought this was an EGR issue.

Sean

 

Oops EGR to much reading diagrams

 

That's ok. I thought that may of been what happened.
We have alphabet soup with all the acronyms.

Sean

 

Found the pinpoint test info it looks as if I'm looking for a short to ground or possible a bad PCM.
Wiring is my least favorite thing to do , I'm confused by the language in the diagnostic procedure. I'm kind of guessing at the terminology is what's im assuming below correct
Component side- the egr sensor pins
Harness side - the plug

A little background to how the problem started- I unplugged the Egr and was going to pull it during routine maitenance. Forgot to plug it back in and about a month went bye. Discovered it when I ran a code check and discovered my mistake and pulled the Egr ( grabed the wrong can and cleaned it with brake fluid. Figured I had ruined it so I purchased a new one from advance and installed it. I'm still reading 4 immediate codes all the same a previously posted.
Seems kind of random to Delevop a short but I guess they usally are and I should run through the pinpoint tests and see we're it leads. Anything obvious jump out at anyone I'm missing.

 

Could be the Ground Issue