EEC Relay will not activate

Reply Subscribe

Thread Tools

Search this Thread

Feb 24, 2002 | 08:27 PM

cyberbyrd

Thread Starter

Senior User

Joined: Feb 2002

Posts: 258

Likes: 0

From: Allegan Michigan

EEC Relay will not activate

89 F250 351W. The EEC relay will not kick in on my truck. I have jumped the wires from the contacts in the relay and the truck starts and runs fine. If I check for voltage at the coil of the relay I have full voltage there, 12VDC or whatever the battery has in it at the time. I have tried two new relays from Autozone and neither of them work. Looking through the wiring diagrams in my Hanes manual I don't see anything else that could be causing the relay not to kick in. I am lost as to what could be causing the problem and am looking for any ideas that you might have. I do have to wonder are these relays full 12VDC coil or are they supposed to operate at a lower voltage via a resistor or something that the manual is not showing.

Thanks

Mar 1, 2002 | 12:23 AM

Electric1

Junior User

Joined: Dec 2001

Posts: 89

Likes: 0

EEC Relay will not activate

CyberByrd,
These relays operate on 12 volts and there is no resistors or ballasts involved here, the E.E.C. computer grounds the E.E.C. relay upon cranking the engine over by the key. It's late here on the East coast, I will look at the chart tomorrow and give you the rest of the story, don't throw anymore parts at your truck,
Electric1

Mar 1, 2002 | 08:08 AM

tomaconda

Freshman User

Joined: Mar 2002

Posts: 29

Likes: 0

EEC Relay will not activate

Hi people.. 1st post.. I'm new and was Ford Tech for 16 years..
There could be many reasons for this symptom but I'd look first for a corroded factory splice in the EEC power relay wiring..the splice goes bad and you get no EEC relay power-up. The splice is in the harness on drivers side under the hood and runs along the fender wall and near the battery where years of acicidy get into the loom.. I'd rip apart that harness and pull offf any tape you see..thats where the splices are.. it may not be the problem but I'll bet there is a bunch of green corrosion there .. You may have to to more testing to see if the relay is getting +12V and or itf the ign. switch is pulling the relay in or whatever.. good luck!.

Mar 1, 2002 | 10:30 PM

Electric1

Junior User

Joined: Dec 2001

Posts: 89

Likes: 0

EEC Relay will not activate

I knew as soon as someone jogged my memory a little it would come to me also, make sure you check right at the E.E.C. relay underneath in the wire connector, check for green corrosion also have seen the wires corrode off inside the connector to the relay. The ground for the relay taps on to the left fender behind the headlamp. Power to drive the relay does come from the ignition switch as mentioned above and goes straight through to ground on the other side of the relay coil, hence pulling it in and cycling the Fuel Pump relay. Check the connector terminals inside and make sure they fit tight on the relay terminals, take alittle time and get the terminals out of the connector and tighten them up by probing through the back side of the terminals, you'll see what I mean once you get them out.
Electric1

Mar 2, 2002 | 06:11 AM

cyberbyrd

Thread Starter

Senior User

Joined: Feb 2002

Posts: 258

Likes: 0

From: Allegan Michigan

EEC Relay will not activate

Thanks you pointed out what I was looking for the ground point for the relay. Several people were saying it was a ground switching action from the computer but my Haynes book was showing it like you described. I will tear into it as soon as this #@$##@ snow storm passes. (don't have a garage)

Thanks again

Mar 6, 2002 | 07:12 PM

cyberbyrd

Thread Starter

Senior User

Joined: Feb 2002

Posts: 258

Likes: 0

From: Allegan Michigan

EEC Relay will not activate

Ok I found the problem. I stoped at NAPA today and picked up another relay from them and pluged it in and everything works fine. Who would figure that I would get two bad relays from Autozone. Now for the fun of trying to get my money back from Autozone.

Thanks for the help guys

Mar 6, 2002 | 10:44 PM

Electric1

Junior User

Joined: Dec 2001

Posts: 89

Likes: 0

EEC Relay will not activate

Cyberbyrd,
that is some good luck you have, but try this one on for size, I ordered a remanufactured engine for a Cadillac Eldorado front wheel drive, it was to be shipped within 5 days of receipt, to find out 2 weeks had gone by and no engine, called Co. was lost in shipment, what are the chances of loosing and engine. Anyways engine remanufacturing Company to rebuild 2nd unit, get engine in 26 days after reciept, install longblock engine, run for 3 minutes, hear pounding sound inside of engine, took 3 hours to get off oil pan to find 7 connecting rod bearing caps were never torqued up, all finger loose, hows that one for a return, took a day to get it out and 1 1/2 days to get in. Electric1