I recently had my truck in the Ford dealer because my battery would not last longer than a week or so without running the truck. They diagnosed it as the fuel pump relay energizing at times throughout the night. They replaced the whole fuse block assembly as the fuel pump relay is one of several not replaceable.

My question is if this relay is not replaceable how were they able to disable it to pinpoint it was the problem?

 

its not just a fuse box. its a smart junction box, kindof like a module and has the ability to self diag and throw DTCs if a problem is present.

 

So i guess my question is how were they able to tell the non removable relay was the problem. the worksheet says they had a ampmeter hooked to the truck overnight.

 

you would be amazed at some of the pinpoint tests that are in the workshop manual. most likely found it through a pinpoint test and disconecting certain connectors untill the draw was within spec. also alot of time what you will see writtin and what the service adivisor tells you is not even close to the whole story especially if its warranty.

 

Paralyzer do you work at a Ford service department? Just curious you seem very knowledgable.

I have the 3 volume service manuals and the pinpoint tests to locating draw just say to remove *fuses* one at a time until the draw is found.

 

Does each relay have a fuse associated with it? it would appear that way accoring to the CJB diagram. So i am guessing you pull the pump relay fuse and thay cuts off power to the relay correct?

 

yes i am a mechanic at a ford dealership. not licenced yet...one more year to go . yes there should be a fuse for the relay sometimes even 2(one for the controll circuit also)

 

have you ever heard of the problem I am having? They replaced the entire fuse box but I think i still have a draw on my battery, i think. It has gone from 12.32v after shutoff to 12.35v and the latest reading was 12.34v about 5 hours after shutdown. I suspect overnight it will drop even more.

 

it is easy enough to check for yourself. do you have a DVOM(voltmeter with Amp setting)?

 

I have this meter. It measures current, I believe that is amp setting you are refering to.

http://www.radioshack.com/product/in...entPage=search

 

that will work. here is what you do. make sure your doors are closed and all aftermarket accessories unpluged and everything else turned off. disconect negative battery cable. with the meter on the 10A scale (and the leads in the right place on the meter)put one lead to the negative post and one lead to the negative cable(dont worry if it reads negative you can switch the leads if it really bothers you) let it sit for at least half an hour untill all the modules power down and you will have your draw reading.

i usually use a pair of vise grips lightly clamped on the negative post and some aligator clips to hold the leads on.

 

ya the guys in my other thread have told me all about how to do it. Problem is first time I tried it blew the fuse in my meter, so JackandJanet walked me thru how to use jumper cables to keep the circuit alive and prevent the fuse from blowing.

If my battery is any lower I will attempt to test draw myself.

 

Do you leave the meter on during those 30 minutes?

 

yes. also your battery is low at only 12.3 volts. about 50% charge. it could be a weak battery causing you issues also. take it from me the factory ones are crap.

 

It is a brand new Optima red top.