Relay Question
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Senior User
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OK, if the fuel pump relay went, I'd still get spark,- right??
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gotta find out some info on how this EEC relay works..
Thanx.
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Thats what I think I'm Lookin at..
-So..
When I turn the Key, It engages the EEC relay Then sends 12v to the fuelpump relay, and also sends power to the Distributor, which then sends power to the coil,??? correct??
Ive gotta find out how power works between the Key, and the Distributor/Coil
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Lead Driver
Joined: Nov 2002
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From: Concord, NC
If the EEC relay fails, there will not be power at the coil, the IAC, the injectors, or the TAD, TAB, and EVR solenoids. As said before, it also supplies the hot side of the turn-on coil in the fuel pump relay. Without a working EEC relay, the engine will spin on starter power only.
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If the EEC relay fails, there will not be power at the coil, the IAC, the injectors, or the TAD, TAB, and EVR solenoids. As said before, it also supplies the hot side of the turn-on coil in the fuel pump relay. Without a working EEC relay, the engine will spin on starter power only.
Would a bad EEC relay prevent me from pulling codes?
Lead Driver
Joined: Nov 2002
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From: Concord, NC
Would a bad EEC relay prevent me from pulling codes?
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-I know their cheap enough to replace, But I'm still not sure if these are my problem-It is pointing this way, But..-What else would do this?-No codes, crank but no start, no spark at coil / Dist....
My Ignition actuator rod is toast, but I can still get the engine to crank with the rod-(The actuator happened to crumble on me during this entire Fiasco..)
the Ignition switch down on the steering column wouldn't smoke a relay would it???
Elder User
Joined: Feb 2008
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From: ohio
The best way is to change them and check for power at the yellow wire going into the relay. If u have power there relay is most likely the problem. If u have No power check the wire that feeds from starter solonoid which i believe to be yellow, for a broken fusable link
Lead Driver
Joined: Nov 2002
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From: Concord, NC
With the key on, there should be +12V at three out of four wires on the EEC relay connector, assuming that the relay is plugged in. With the relay unplugged, only two. The fourth wire should have continuity to ground if I'm remembering the wiring diagram correctly (no guarantees -- it's been a while).
Elder User
Joined: Nov 2008
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From: Northfield, MI
A really quick check is to see if your "Check Engine" light comes on when you turn the key. This light is turned on by the PCM. If the light comes on, the PCM relay is working and the PCM is getting power. It doesn't tell you if you have a wiring problem and whether or not all of the other components are getting power, just the PCM.
For the fuel pump relay, if you can't hear the pump run when you turn the key on, check for power at the inertia switch with an incandescent test light. The pump only runs for a couple of seconds, so cycle the key while checking. Power there means the PCM and fuel pump relay are working. If power is good and you don't have fuel pressure, pull the connector at the pump and check for power there. The power wire is usually pink with a black stripe on most Ford vehicles, but not always.
For the fuel pump relay, if you can't hear the pump run when you turn the key on, check for power at the inertia switch with an incandescent test light. The pump only runs for a couple of seconds, so cycle the key while checking. Power there means the PCM and fuel pump relay are working. If power is good and you don't have fuel pressure, pull the connector at the pump and check for power there. The power wire is usually pink with a black stripe on most Ford vehicles, but not always.