Data bus problems
Thread Starter
|
New User
Joined: Aug 2015
Posts: 20
Likes: 0
Data bus problems
I have a 2004 6.0 with no communication with the abs, and the multi function module, and a code for j1850 fault and scp+ fault. I've chased the 2 wires from the mf module to the dlc, to the abs with good continuity on both, I've also tested both from the ficm to the pcm with good continuity, but have no continuity from the abs or the dlc to the pcm or ficm. Does anyone have a diagram of the routing of these wires, or know where they run to? I've spent many hours chasing these wires and searching online for pinouts and wiring diagrams and just can't seem to figure out how they are routed between the 2 ends. I'd love to just jump from the pcm end to the abs but I'm not sure that's a good idea.
Thread Starter
|
New User
Joined: Aug 2015
Posts: 20
Likes: 0
Solved it!
I have a 2004 6.0 with no communication with the abs, and the multi function module, and a code for j1850 fault and scp+ fault. I've chased the 2 wires from the mf module to the dlc, to the abs with good continuity on both, I've also tested both from the ficm to the pcm with good continuity, but have no continuity from the abs or the dlc to the pcm or ficm. Does anyone have a diagram of the routing of these wires, or know where they run to? I've spent many hours chasing these wires and searching online for pinouts and wiring diagrams and just can't seem to figure out how they are routed between the 2 ends. I'd love to just jump from the pcm end to the abs but I'm not sure that's a good idea.
Hotshot
Joined: Jan 2004
Posts: 19,760
Likes: 1,079
From: St Louis
Fuse F12 doesn't have anything to do with any of the data buses. It does, however, supply power to, in addition to the lighter, pin 16 of the DLC which is used to power a connected scan tool for those tools that do not have their own built-in power supply.
Unless you have a scanner with it's own power, your symptom should have been "scanner won't power on when connected" or the like.
Unless you have a scanner with it's own power, your symptom should have been "scanner won't power on when connected" or the like.
Thread Starter
|
New User
Joined: Aug 2015
Posts: 20
Likes: 0
Scanner power and scp bus
First off my scanner has its own power. Second the Scp+ bus is powered by that fuse also, which is part of the data bus, and why I had a j1850, and scp bus fault. So my title is in fact acurate.
Hotshot
Joined: Jan 2004
Posts: 19,760
Likes: 1,079
From: St Louis
They're not wrong. Ford has used pretty much the same implementation for the bus and how they work for a number of years. If this diagram is wrong, so are all the rest across multiple model lines and production years. You figure the odds of that level of error. However, you may have assigned an effect to an unrelated cause so, who knows? Pull the fuse back out and see what happens. Perhaps your scan tool isn't as fully self-powered as you might have thought.
FWIW, Ford's SCP bus uses the J1850 bus. It connects the PCM, the cluster, and, for a diesel application, the APCM together.
Anyway, I'll just caution future readers to treat your report of the "solution" with a healthy dose of skepticism
FWIW, Ford's SCP bus uses the J1850 bus. It connects the PCM, the cluster, and, for a diesel application, the APCM together.
Anyway, I'll just caution future readers to treat your report of the "solution" with a healthy dose of skepticism
Trending Topics
Thread Starter
|
New User
Joined: Aug 2015
Posts: 20
Likes: 0
My report of a solution.
My report of a solution was directed by trouble shooting the circuit following Snap-on diagnostic routine. Treat it how ever you like. The facts are I had no communication with 2 modules with a modis scanner which is fully self powered, when I repaired the wire supplying fuse #12, I got communication back and the j1850 fault code and scp+ fault code went away, and my HEC and PCM regained communication with the ABS, and MFM. I used Fords pinpoint test to no avail, wasting hours of time.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Ford Super Duty: 5 Things Owners LOVE, 5 Things They LOATHE!
Joe Kucinski
Every 2026 Ford Truck Engine RANKED from WORST to FIRST!
Michael S. Palmer