relays under fuse box clicking

[grease mnky]

Anybody had an issue with relays continuously clicking with koeo want start either fuel pump relay is one that is clicking eec is not and i dont know what the green relay is.

 

[holyford86]

what?

 

[hidesertrat]

Sounds like you may have lost the "holding path" for the relays. Once the key is turned on it energizes the relay, once this happens there needs to be a signal to hold the relay on.

The biggest help with this would be if we knew what year of ranger you have, each one is wired a bit different.

For those who didn't understand "koeo"......Key On Engine Off. and the truck won't start either.

 

[grease mnky]

thanks it is a 1991 standard cab 4 wheel drive. It will crank but it cuts off pretty quick or misses to the clicking of the relays. I am a Machanic of a 200 car fleet of chevys so I am a little out of my expertice so a little help will get me going down the right path. I figured I would get some help instead of throw parts at it.

 

[MAKG]

Does it crank normally?

Sounds like a low battery to me.

PLEASE try to communicate more clearly. This is a written medium, and it is fairly presumptuous to expect us to decipher yours.

 

[holyford86]

 

[grease mnky]

Ok under the fuse box under the hood passanger side there are 3 relays the black, the brown and the green. I have checked the ground to the relays they are good. The battery is fully charged. The relays are turning on and off rapidly they they may stay on for 30 seconds are so, then may go off for 30 seconds are so then start turning off and on rapidly. This does vary some. When the relays stay on the truck will crank and run. Then while it is running the relays loose power and the truck will cut off all together or skip if the relays are coming on and off rapidly. Also the check engine light with koeo will flicker to the sound of the relays on and off clicking.

 

[Psychopete]

I THINK that the green is fuel, brown computer, and black A/C. Unplug either the brown or green, if you have spark, then you unplugged the fuel pump relay. If not, computer relay.

The computer relay is probably causing the fuel pump relay to rapidly switch on/off (but very possibly not directly, eg. loose wire/problem at power distribution box, battery terminal?). The fuel pump relay is turned on when the computer relay turns on, and computer starts to prime the system twice for about 2 sec. each. Wiring diagram would help.

Pete

 

[pillen140]

are you doing this with a battery charger hooked up to it? or is the battery actually fine? i know you said its fully charged, but does that mean with the charger on it?

 

[hidesertrat]

I don't have wiring diagrams for 91, but did have some for 90. So if they are close or possibly the same, this may help.

The EEC relay in energized by a red/Lt grn wire coming from you ignition switch. It than passes voltage from the yel/blk wire to the red wire. This red wire will energize the fuel pump relay.

I would look at the voltage on the red/lt grn wire of the EEC relay and see if it is intermitent, possible you have a bad ignition switch. Or you could short the yel/blk wire to the red wire and see if the truck will run.

I am guessing this is going to be your problem, so no need to go into any more options.