Ok guys. I'm back to bother all of you some more. I got a 2007 6.0 with an intermittent no start condition. We will be going down the road and the engine will just cut out. Used my torque app and found that the ficm doesn't seem to be getting power from the truck. When it is running, the ficm is 48v and logic is 12. When it dies, there is no injector buzzing and no voltage read outs when cranking. After messing with the ficm relay, I got it started but it died on the way back home. I am believing that this may be the ficm relay. I have double checked that the harness is plugged in good to the ficm and haven't found any chaffing yet. Any ideas?

 

FICM Relay sound's like the first place to look , check V-ref volts too , are all the connections snapped in tight ? no Broken clips?

 

All of the connectors to back of ficm are in and tight. Is it common for these relays to fail?

 

corrosion from off the Battery ,water Intrusion could mess with it. is the Plastic battery cover still on it helps cover the PCM

 

Also there was a Thread on the relay Ed at Ficm repair was saying the relay does get heated and loose the juice needed, I think I might get one from Ed soon, If I remember correctly when unplugged look at the bottom if brown crusty looking then it's time

 

Yes. The plastic cover is still in place. The bottom of the relay doesn't look brown or crispy. I have 12v power to 2 connection where the relay goes.

 

Swapped relays from a running truck and no difference. The relay out of this truck worked on mine as well.

 

Here are some things to try:


1. Replace FICM relay & check all fuses.

With the FICM unplugged and out of the way

2. Check voltages and grounds at all relay terminals
3. Check continuity between pin 5 of FICM relay socket and pins 4, 23, 24 & 25 on the x3 plug
4. Check continuity between the negative battery terminal and pins 1,2, 3, 22, & 26 on the x3 plug.
5. KOEO force ground the ground terminal of the FICM relay and check voltage at pins 4, 7, 23, 24 & 26 on the x3 plug
6. Plug in the FICM (x3 only) and check voltage on the second from the right (drivers seat orientation) test terminal.
7. Plug in the FICM (x3 only) and check voltage on the second from the right (drivers seat orientation) test terminal.
8. Check continuity between the two left side test terminals and the negative terminal of the battery.

No volts at some of the above x3 plug pins could indicate a harness issue between the relay & the FICM, no volts at pin 7 is something between the FICM and the ignition switch, no continuity between x3 and the negative terminal of the battery could be a harness issue or a flaky ground connection.

 

Wire chaffing under the FICM has been a common issue.