The Diesel Garage banner

1 - 5 of 5 Posts

·
Registered
Joined
·
253 Posts
Discussion Starter #1
I just finished installing a better ECM in my early '99. It is still a stocker, but the truck drives and shifts so much better. :Thumbup: After installing the ECM my truck fired right up and test drove great. However after a few cycles of the ignition, I now have the SES light on showing the following code: P0683 "Glow plug control module to PCM communication circuit". I cleared the code but it came back a few starts later. The truck was running excellent before the ECM swap and had no issues. The truck now starts and runs excellent after the swap as well. Any ideas where to start looking/testing?

Secondly, the "Water in Fuel" dash light is staying on continuously with the new ECM. It never even lit up before (even during initial key on) with my old ECM. I drained the water seperator as mentioned in the manual, but the light is still staying on (BTW, I found no water in the fuel). No other codes showing except the above. Any ideas? Thanks in advance.
 

·
Registered
Joined
·
253 Posts
Discussion Starter #2
Anyone??
 

·
Registered
Joined
·
253 Posts
Discussion Starter #3
Ok, I'm on to something here, but still need help.....The early 99 F250's in CA came with a "glow plug relay" and then the CA 2000's and up came with a "glow plug control module". This is a solid state set up and is a little different than a gp relay. The newer glow plug control module has a commnication line (wire) that sends info to the ECM all the time about the glow plugs condition, etc. Since I installed a newer model year ECM today, in an early 99 with old style relay, the ECM is not getting the "communcation" it wants through the "line". Which

I read somewhere else that you can upgrade to the new glow plug control module and harness. My main question: is there already a "communication" line going to my ECM from the old gpr that I will be able to use if I upgrade harnesses and gpcm from the newer trucks? Hope this makes since, thanks.
 

·
Registered
Joined
·
1,181 Posts
Action Rick said:
You may be able to have the new PCM reflashed to work without changing to the GPCM ....

:iagree

Shift improvements can be made with a valve body also. Consider a tuner or chip vs. the cost of re-flash or conversion to achieve your goal.


.
 
1 - 5 of 5 Posts
Top