RELAY PROBLEM PLEASE HELP.
Thread Starter
|
Senior User
Joined: Mar 2014
Posts: 105
Likes: 0
RELAY PROBLEM PLEASE HELP.
I recently had a problem with my truck turning off on the highway. It would crank back up but once it got home and parked it died and would only turn over. Had a mechanic come over and he replaced the IDM relay and it cranked and ran GREAT )Dead for over a month). My question is why would the relay blow stop working? If it's a short where do I even start.
Cargo Master
Joined: Oct 2003
Posts: 2,833
Likes: 4
From: Jefferson, Iowa
The 6.0 has a FICM not an IDM. Relays can just fail, they are a mechanical part. So what your saying is right now you have replaced the FICM relay, it ran for a little bit, now it just cranks. Correct?
Lead Driver
Joined: Sep 2012
Posts: 7,821
Likes: 93
From: Manteca,Ca
I recently had a problem with my truck turning off on the highway. It would crank back up but once it got home and parked it died and would only turn over. Had a mechanic come over and he replaced the IDM relay and it cranked and ran GREAT )Dead for over a month). My question is why would the relay blow stop working? If it's a short where do I even start.
Fleet Owner
Joined: Apr 2012
Posts: 27,307
Likes: 549
From: Spanaway
Relay failure could be because of loose connections in the BJB (Battery Junction Box)
where the FICM relay is located. A loose connector tends to get worse do to the fact that
is it loose and will have some heating do to current and higher resistance at that
connection. You need some type to tool ie a gauge set that will read live data so you
can see what the numbers are for each thing that would need to be checked and verified.
FICM main power being one of the things along with logic power and so on.
If the FICM is not getting main power or battery voltage then it's back to the relay or
the connector plugs.
Sean
where the FICM relay is located. A loose connector tends to get worse do to the fact that
is it loose and will have some heating do to current and higher resistance at that
connection. You need some type to tool ie a gauge set that will read live data so you
can see what the numbers are for each thing that would need to be checked and verified.
FICM main power being one of the things along with logic power and so on.
If the FICM is not getting main power or battery voltage then it's back to the relay or
the connector plugs.
Sean
Trending Topics
Thread Starter
|
Senior User
Joined: Mar 2014
Posts: 105
Likes: 0
No it ran fine and randomly shut down on the highway. It started back up and drove home then it cut off right when I parked it. At that time it would only turn over. It sat for a while until I could get a mechanic out to look at it. The last resort he tried was to swap the blower relay with the IDM and then it started right up. When it was running my AC wouldn't blow anymore so that prooves the one that he swapped and put in the blower spot is broke. But why would any of that even happened? I know relays can fail but it's like this one sometimes worked and sometimes didn't. It was the original relay in that spot I believe. 280,000 miles
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
The Best F-150 Deal of Every Trim Level (XL through Raptor)
Joe Kucinski
Thread Starter
|
Senior User
Joined: Mar 2014
Posts: 105
Likes: 0
Relay failure could be because of loose connections in the BJB (Battery Junction Box)
where the FICM relay is located. A loose connector tends to get worse do to the fact that
is it loose and will have some heating do to current and higher resistance at that
connection. You need some type to tool ie a gauge set that will read live data so you
can see what the numbers are for each thing that would need to be checked and verified.
FICM main power being one of the things along with logic power and so on.
If the FICM is not getting main power or battery voltage then it's back to the relay or
the connector plugs.
Sean
where the FICM relay is located. A loose connector tends to get worse do to the fact that
is it loose and will have some heating do to current and higher resistance at that
connection. You need some type to tool ie a gauge set that will read live data so you
can see what the numbers are for each thing that would need to be checked and verified.
FICM main power being one of the things along with logic power and so on.
If the FICM is not getting main power or battery voltage then it's back to the relay or
the connector plugs.
Sean
Thread Starter
|
Senior User
Joined: Mar 2014
Posts: 105
Likes: 0
It held up for 280,000 miles so it wasn't like it was brand new. Do relays just go bad over time? And even if they do how would that explain why it would die but start back up. Can they relay work sometimes and not?
Hotshot
Joined: Dec 2003
Posts: 15,368
Likes: 121
From: Stuttgart, Ar
Yes, they do go bad over time. Probably the FICM/IDM relay pictured here:
Fleet Mechanic
Joined: Aug 2012
Posts: 1,760
Likes: 21
Relays do fail. The contacts can "weld" themselves together or get build up on them and not make a good connection. The coil inside can also fail open from a broken or burnt wire inside.
Once you have replaced it with a new one crack it open and have a look see.
.
Once you have replaced it with a new one crack it open and have a look see.
.
Cargo Master
Joined: Oct 2003
Posts: 2,833
Likes: 4
From: Jefferson, Iowa
repeated closing of a relay into a faulted circuit can ruin the contacts. You would also have several blown fuses and such. I would replace the relay and call it good. I am an electrician by day and this sort of thing happens, anything mechanical wears.