Looking for information on relays getting hot,
seems there's a lot of opinions. My 99' F-150 started acting up when turning off at operating temp upon opening the door complete electrical turn off in a few seconds the pcm relay under the driver dashboard starts clicking generally pressing the brakes it seems to reset itself and will start no problem. The relay was pretty warm to the touch. So,
Changed out relay problem solved.. I think so, but notice the relay still gets pretty warm...
Is this normal? It is an electromagnet so in theory it should get warm.

 

First where did you find a PCM relay on the dash fuse panel?
The relays 1, 2, 4, and 5 have nothing to do with the PCM.
The PCM relay is in the engine bay as #501.
ID which relay and in what panel your talking so we can tell the circuit being controlled by it.
It may be normal for it to be operated for long periods until shut off by a module with a timer that goes into sleep mode after about a half hour +/-.
Good luck.

 

Under the driver side dashboard passenger compartment fuse panel. The #2 5amp relay is according to the owners guide F-150/250 1999 model year is the Powertrain Control Module (PCM) Cluster.
When I turned the truck off last night after installing a new relay I look this morning relay clicking and all electric was off including the Pats light, checked my battery, 12.67vdc.
After fiddling with the the key and r&r the relay, moving the the shifter etc etc . The electric came back on.
Thanks Mickey

 

The PCM Relay is under the hood.

Do you even know the difference between a relay and a fuse???

 

Please don't insult me.

Moderators please close this thread.
Thank you,
Mickey

 

If what you are working on is the #2 relay in the under dash fuse box, and that is the one that is getting hot; that relay is the battery saver relay. On my trucks of this generation, opening the door has always shut down most or all of the power to stuff like power windows. The lights stay on for so many minutes, and then power to this relay times out and is cut off so all the circuits it feeds stop working.
The original style incandescent festoon dome light bulbs tend to get very hot when lit, so this may account for some of the heat. Or there may be another circuit that has issues fed by that relay. You will need to figure out what is not working correctly or not lighting when it should be in order to effectively diagnose this further.

Any occupied position in a "fuse box" noted in the Ford owners manual with an Amperage rating will usually be a fuse or some other type of circuit breaker for overload protection. The relays are also usually called out as relays in the description as are diodes.
A relay does have a specified maximum Amp rating, but that rating is not listed in your vehicle owners manual to avoid confusion. For the most part, Ford uses different pin configurations to keep anyone from plugging in a relay with too low of a rating into the wrong spot. If you will notice, some relays have the "blade" connector pins set 90° from each other. This is so that a relay with a specific pin configuration and rating will only fit into its correct connector to avoid accidentally using the wrong relay for a particular circuit.

It appears that you may have misread the diagram for the inside fuse box, because
"#2 5A Powertrain Control Module (PCM), cluster"
means that the fuse in the designated #2 spot feeds the PCM and also feeds the gauge cluster. There is no PCM cluster.
The key to the fuse diagram is continued on the next page, which is page 154 in the online copy I viewed. It has the relay descriptions for that fuse box on the next page (154). So I understand how it could be a simple mistake to see almost the whole fuse box diagram on pages 152 & 153 and not realize that it is continued on the next page.

This is incorrect according to the owners manual that I downloaded here:
http://www.fordservicecontent.com/Fo.../99f12og1e.pdf
It shows that for a 1999 F150, 501 is the PCM diode and the PCM relay is 304.

Everyone makes mistakes.

 

Thank you Sam, my problem is parasitic electrical draw. Yes, not everyone gets terminology correct.

 

Mickey?

Did you ever figure out that parasitic electrical draw?? I'm having issues also.