Help! Weird EEC Relay Problem!!!
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Senior User
Joined: Aug 2007
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Help! Weird EEC Relay Problem!!!
Hi,
I've had a "crank no start " problem for a while now.
It actually was a couple of things.
This is on a 1989 F-150 4.9L 2WD truck.
On the eec relay there is a "high current" 12V coming from a fuse link at the starter selinoid.
This wire back probed at the EEC Relay Connecter is B+ voltage as it should be.
However the "high current" out is only 4.9V!!!
The "low current" voltage coming from the ignition switch is 11.8V.
I have changed the EEC Relay, the eec connector AND the ignition switch.
Still only getting 4.9V out of the high current supply (out) wire????
The ground is good also!
Just to check I took my Power Probe 3 and applied B+ power to the high current out as it is suppose to have and the engine started!!!
I think if I can figure why the power out wire is not getting the full voltage from the high current supply wire I will have this fixed!
Testing by the book it calls this a BAD relay but that is not true in this case?
Strange I know but looking for ideas!!!
Any help on this is appreciated!!!
I've had a "crank no start " problem for a while now.
It actually was a couple of things.
This is on a 1989 F-150 4.9L 2WD truck.
On the eec relay there is a "high current" 12V coming from a fuse link at the starter selinoid.
This wire back probed at the EEC Relay Connecter is B+ voltage as it should be.
However the "high current" out is only 4.9V!!!
The "low current" voltage coming from the ignition switch is 11.8V.
I have changed the EEC Relay, the eec connector AND the ignition switch.
Still only getting 4.9V out of the high current supply (out) wire????
The ground is good also!
Just to check I took my Power Probe 3 and applied B+ power to the high current out as it is suppose to have and the engine started!!!
I think if I can figure why the power out wire is not getting the full voltage from the high current supply wire I will have this fixed!
Testing by the book it calls this a BAD relay but that is not true in this case?
Strange I know but looking for ideas!!!
Any help on this is appreciated!!!
Fleet Owner
Joined: Oct 2005
Posts: 20,789
Likes: 1,753
From: Kentucky
Hi,
I've had a "crank no start " problem for a while now.
It actually was a couple of things.
This is on a 1989 F-150 4.9L 2WD truck.
On the eec relay there is a "high current" 12V coming from a fuse link at the starter selinoid.
This wire back probed at the EEC Relay Connecter is B+ voltage as it should be.
However the "high current" out is only 4.9V!!!
The "low current" voltage coming from the ignition switch is 11.8V.
I have changed the EEC Relay, the eec connector AND the ignition switch.
Still only getting 4.9V out of the high current supply (out) wire????
The ground is good also!
Just to check I took my Power Probe 3 and applied B+ power to the high current out as it is suppose to have and the engine started!!!
I think if I can figure why the power out wire is not getting the full voltage from the high current supply wire I will have this fixed!
Testing by the book it calls this a BAD relay but that is not true in this case?
Strange I know but looking for ideas!!!
Any help on this is appreciated!!!
I've had a "crank no start " problem for a while now.
It actually was a couple of things.
This is on a 1989 F-150 4.9L 2WD truck.
On the eec relay there is a "high current" 12V coming from a fuse link at the starter selinoid.
This wire back probed at the EEC Relay Connecter is B+ voltage as it should be.
However the "high current" out is only 4.9V!!!
The "low current" voltage coming from the ignition switch is 11.8V.
I have changed the EEC Relay, the eec connector AND the ignition switch.
Still only getting 4.9V out of the high current supply (out) wire????
The ground is good also!
Just to check I took my Power Probe 3 and applied B+ power to the high current out as it is suppose to have and the engine started!!!
I think if I can figure why the power out wire is not getting the full voltage from the high current supply wire I will have this fixed!
Testing by the book it calls this a BAD relay but that is not true in this case?
Strange I know but looking for ideas!!!
Any help on this is appreciated!!!
Thread Starter
|
Senior User
Joined: Aug 2007
Posts: 371
Likes: 4
Hi,
Not my thread???
As I stated above, I have B+ voltage going in the relay and only 4.9V coming out???
Makes no sense, what I was told, is it might be corrosion on the ignition switch effecting switch power from there.
I replaced the ignition switch with a MOTORCRAFT part and still no change.
Admittedly I'm out of ideas on this and seems everyone else is too.
I'm wondering now if I can just "hot wire" it to get it home or to a Dealership?
It will start and run when I supply B+ with my power probe!
Not my thread???
As I stated above, I have B+ voltage going in the relay and only 4.9V coming out???
Makes no sense, what I was told, is it might be corrosion on the ignition switch effecting switch power from there.
I replaced the ignition switch with a MOTORCRAFT part and still no change.
Admittedly I'm out of ideas on this and seems everyone else is too.
I'm wondering now if I can just "hot wire" it to get it home or to a Dealership?
It will start and run when I supply B+ with my power probe!
Fleet Owner
Joined: Oct 2005
Posts: 20,789
Likes: 1,753
From: Kentucky
Must be your evil twin:
https://www.ford-trucks.com/forums/1...y-problem.html
More threads on the same topic:
https://www.ford-trucks.com/forums/1...d-voltage.html
https://www.ford-trucks.com/forums/1...-no-spark.html
We are trying to help you, but jumping to new threads without following through on the old ones is making it tough on you and the rest of us.
https://www.ford-trucks.com/forums/1...y-problem.html
More threads on the same topic:
https://www.ford-trucks.com/forums/1...d-voltage.html
https://www.ford-trucks.com/forums/1...-no-spark.html
We are trying to help you, but jumping to new threads without following through on the old ones is making it tough on you and the rest of us.
Fleet Owner
Joined: Oct 2005
Posts: 20,789
Likes: 1,753
From: Kentucky
Some good advice in this post from that previous thread: https://www.ford-trucks.com/forums/1...l#post17555520
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Thread Starter
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Senior User
Joined: Aug 2007
Posts: 371
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Hi,
Thanks rla2005!
I went back and answered that thread.
As I said there, I have been all over the Internet trying to get a handle on this as TO ME made no sense?
I obviously lost track of that thread....THANKS AGAIN!
Thanks rla2005!
I went back and answered that thread.
As I said there, I have been all over the Internet trying to get a handle on this as TO ME made no sense?
I obviously lost track of that thread....THANKS AGAIN!
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Fleet Owner
Joined: Oct 2005
Posts: 20,789
Likes: 1,753
From: Kentucky
Personally I think your high impedance DVM is lying to you. You are reading a phantom voltage on an open circuit.
As mentioned in the other thread run a temporary fused line to the supply side of the EEC relay. The truck should start. You proved if you ran power to the load side tge truck started. Let's get a known good power source to the load side to prove the relay is getting energized and the supply/load contacts are good.
Thread Starter
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Senior User
Joined: Aug 2007
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Glad we could point you in the right direction.
Personally I think your high impedance DVM is lying to you. You are reading a phantom voltage on an open circuit.
As mentioned in the other thread run a temporary fused line to the supply side of the EEC relay. The truck should start. You proved if you ran power to the load side tge truck started. Let's get a known good power source to the load side to prove the relay is getting energized and the supply/load contacts are good.
Personally I think your high impedance DVM is lying to you. You are reading a phantom voltage on an open circuit.
As mentioned in the other thread run a temporary fused line to the supply side of the EEC relay. The truck should start. You proved if you ran power to the load side tge truck started. Let's get a known good power source to the load side to prove the relay is getting energized and the supply/load contacts are good.
Hmmm...Thats a new one on me?
Yes I could run a wire to the relay and see if that fixes it?
I have to charge my battery but should be able to do that tomorrow.
Thanks again, I'll get back and tell you what happens!
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