Hello Fellow,

Now that I believe the #2 PCM relay is going out and should be replaced, is this a dealer item, and is it safe to pull it out of the wiring block without disconnecting the battery? So far I've driven the truck a few miles and stopped/started at least 4 times.

Thanks again,
Jack

 

any parts store should have them, and technically anytime yoou do something with the electrical you should disconnect the battery,

 

Well, I checked Auto Zone and Advanced Auto for the PCM relay and they don't even list it as a parts item in their system. Of course, you're talking about low-end parts stores. A "kid" at Auto Zone said go to NAPA. I'll probably just go to the dealer...

-Jack

 

if you take the part in there they can match it, those people are use less for the most part

 

tell them you need this part number 19273, I found that part number on the website for the store you went to, a relay is a relay for the most part I haven't looked but the relay your talking about is a square one or a smaller rectangular one?

 

Thanks, Dan. You are correct. It's clearly on their website, but the "kid" couldn't find the relay for the PCM unit. I'll go back with their website printout as seen here: AutoZone.com | | Relay - Control Module

That's the level of service you get sometimes over there, unfortunately. Clueless kids

-J

 

The PCM power relay is in the underhood fusebox, not under the dash.

The underdash fusebox has 5 relays. Using the diagram in the owner's manual, which relay did you tap?

 

Yes, "project SHO89," what I'm calling the PCM relay is not technically correct. What I need to replace is the #2 relay under the dash (not engine compartment distro box) and is a 5A relay as labeled #2 in the owner's manual for the PCM and dash.

In fact I just went outside to start the truck, but it only cranked and didn't start. I wiggled the #2 relay (under the dash) and it started up again. Incidentally, the 'Theft' light blinks as normal when it cranked and started. It blinked rapidly when the truck would not start as part of the PATS system.

Thanks once again,
Jack

 

ok if it's the number 2 relay then it's a smaller relay then the one I sent you the part number to, when you get to the parts store pull the relay take it inside and have them match it up

 

Relay #2 in the CJB is the "Battery Saver Relay" and cannot affect the starting of the engine.

If tapping on it allowed PATS to be happy, I'd suspect that there is an intermittent connection adjacent to the relay and that your tapping of the relay allowed the connection to "make".

Fuses F2, F6, and F30 in the CJB would be logical ones to check for corroded connections or "stretched" contact fingers. Also, look for any evidence of water infiltration that might be causing corrosion inside the fuse panel or GEM module (Leaky Windshield Syndrome).

 

Hey there projectSHO89,

Good tips, as always. I checked the dash fuses you suggested and they check out fine with a continuity meter. You know, your suspicions may be correct about corrosion and "making" contact when I've wiggled the #2 relay. I've since done a Google search under: Ford+GEM+windshield, and have found lots of complaints about Ford knowing about this problem for years. Apparently there's a TSB service bulletin #98-23-1 that addresses this problem with a plastic shield over the GEM. Do you know anything about this?

I checked my carpet and sound deadening material and it seems dry to the touch, but it hasn't rained in over a week, and with me blowing the heater in the cab it may have dried out, too. I can't rule out that the windshield may be leaking until it rains hard again or I put a garden hose to it.

I should point out that when the truck wasn't starting I could hear relay noises coming from under the hood in the main junction box. When the truck does start the noises are absent. At this point, it may be useless to replace the #2 relay under the dash, it would seem, until a more reliable answer for the fix can be found.

Thanks as always,
Jack

P.S. Take a look at what this lady went through back in 2006: http://www.my3cents.com/showReview.cgi?id=15119

 

i just had the same problem today and with u guys help i found out how to get it running. thx alot! i turned the key to the on position and when i popped the hood i was standing on the side of the truck and the relay on the top left i wiggled around and heard a noise. went back to start it up and it cranked right up! i dont know much about vehicles at all but with what u guys were talking about a think i found the problem. thanks alot. u helped me save some cash!

 

Just letting you know that my truck still starts, but I didn't do anything to solve the problem. It's been raining here in Central Texas for a full day, and I can say that inspecting under the floor mat and the firewall I don't see any moisture coming in the cab from the windshield area.

All I've done is wiggle the #2 relay (battery saver) under the dash and it's been starting just fine. Obviously, there's a connection that's not making contact. It does, however, affect the PATS system.

This is an expensive fix and it'd take a really good electrical troubleshooter to actually find the problem, so for now, I'll just let it be until it becomes an issue that the truck won't start when I wiggle the fuse box area.

-Jack

 

So I have the same problem..

its a weird story.. I have owned the truck for a year now, and it never had the issue and it happend like twice, but in the past 2 weeks its happened more and more...

I haven't done any electrical work until my buddy (physics major) started to fool aroudn with it... its not fixed, i still just wait around for it to "decide to work" and it works..

Okay so I am taking this whole thread and saving it to my phone (so i can read it while I am trying to fix it)

My dealership contact just called me (literally 5 minutes ago) to see if they can find a new relay for me... I have a few questions:

1. Are these general relays? or is each relay very specific to its job?

2. is it safe to use relays from different models/years? for example my truck is a f-250 bi fuel V8... If i went to a junk yard and grabbed a relay from a F-150 gasoline only V4 would it work?

3. what is the general price for relays?

Okay thanks guys

-James

 

Relays may be specific as some have no resistors across the coil, some do and some have diodes to prevent back feeds. Best to just look at fuse box relays for size, color and part numbers stamped on them. I've found most fuse boxes have at least two relays with the same part number so I just switch them around and see if the problem is solved and creates a problem for the other circuit I switched with. Of coarse you have to know which relay does what, as for example switching a pcm relay with a fuel pump relay will end up with the same results, no start. Hopefully there are other relays like pwr windows which can be switched with the pcm.