tecanic1 Posted November 4, 2011 Share Posted November 4, 2011 2006 e350 ambulance....hard start... ficm mpwr koeo drops to 18 volts..ficm lpwr koeo drops to 6 volts ficm vpwr koeo drops to 6 volts. koer all are in spec. head lamp load test all voltage supply wires and grounds. tried another ficm with same concern. have followed tsb for this concern per hotline advice with no change. pcm ficm and tcm at lates calibration. load test both frame mount ted batteries and found one bad. replaced battery and still same concern present. engine starts and runs fine other than this ficm voltage concerns. all battery voltages present at ficm connector 1338c. any thoughts would be greatly appreciated..thanks Quote Link to comment Share on other sites More sharing options...
GregH Posted November 4, 2011 Share Posted November 4, 2011 I maintain a fleet of E450 buses with frame mounted batteries. My FICM 12v powers typically drop below 9 volts while cranking, even with new batteries. I chalk it up to the long battery cable run... MPWR drops below 48 volts during crank, but no where near 18V... And the powers jump right back up to where they are supposed to be immediately after engine start... If the engine starts and runs fine, and there are no codes, it may be fixed with that one bad battery. I take it mpwr comes back to 48 volts? Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted November 4, 2011 Share Posted November 4, 2011 If I recall it is considered "normal" for FICM voltages on an E-Series to drop a little. Not a significant amount though. It could be because of the wiring as Greg mentioned. You might also consider checking the battery cables by performing a voltage drop test. Also, did you LOAD TEST the FICM power and ground circuits? Quote Link to comment Share on other sites More sharing options...
Brad Clayton Posted November 4, 2011 Share Posted November 4, 2011 E-box FICM's cannot be tested like F-series using pid data. To truly know what the voltages are will require removing the small cover on the ficm and checking the voltages on the 4 screws. The outer screws will have 48 volts and the inner screw will have batt voltage. DO NOT ALLOW YOUR METER LEAD TO TOUCH THE CASE IF YOU DECIDE TO CHECK THESE VOLTAGES. I bet you that the FICM is ok. Quote Link to comment Share on other sites More sharing options...
Mbl35 Posted November 4, 2011 Share Posted November 4, 2011 Check the power connections mounted on the inside of the battery box. Also check the power connection point on the chassis or the body, usually a foot in front of the battery box depending on the manufacturer. Problobly has alot of corosian. Quote Link to comment Share on other sites More sharing options...
tecanic1 Posted November 4, 2011 Author Share Posted November 4, 2011 Well according to another hotline tech and ford engineer this is normal operation for e series only......when you cycle to key from off to on and watch the pids they drop to more than half of the required voltages. but after about 20 seconds or so they return to normal. per hotline and ford rep this is normal...but there is no written literature stating this... Quote Link to comment Share on other sites More sharing options...
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