Recent Electrical problem from hell... Please help!
11-29-2012, 06:09 PM
#12
teh n00b
Thread Starter
So so far the only thing I have been able to find is a diode under the hood on the drivers side in a relay box. I have no clue what the diode is for but what I do know is that nothing is going through it when I test it with the multimeter both directions.
11-29-2012, 07:04 PM
#13
Originally Posted by swflkr
So I have a 2005 F150 King Ranch SCREW w/ a 2.5" leveling kit, 2011 wheels, 2011 tow mirrors, Edge Evolution, flow master dual exhaust, magnaflow high flow cats, air raid intake, and two kicker 10's under the rear seat with a 250 watt JL amp. All of these modifications have been done for nearly a year.
Now that you know the truck and what has been done, tonight I pulled into the starbucks and I opened up my door and noticed the left side over head dome light was dimming and slightly blinking. I figured a bad connection so I popped it down for a second and went to tighten the little socket to see if it would be a quick fix. Well, that plan back fired and turned into a bad night. All of the sudden none of my accessories work!!!
Here is a list of the inop items:
[*]Air bag light is on[*]No power windows (can't roll them up, currently stuck down)[*]no garage door opener up in the visor[*]no dome lights[*]no radio[*]My "a/c" works... but the actual A/C part does not. I only get heat and the compressor does not kick on[*]no gauges (RPM, speed, fuel, temps, batt ect) although the lights in everything illuminates[*]no reading in my gauges with the miles, mpg ect... you know, the screen.
I checked the fuse box, switched around relays to see if anything changes, pulled out every fuse by hand to physically check them to see if they are bad one by one. Unplugged the battery for 10 minutes. Unplugged the computer in the engine bay also for alittle while... Im pulling up two codes: Fuel level sensor low voltage circuit, and OBD test incomplete or something like that.
I've also had a growing problem with if my door is open, I can not roll my windows up but I believe I know the issue for that from what I was reading about the wires getting chaffed in the door. but thats the least of my worries..
I hope I supplied enough info to bettery help with my diagnostics. I beg for any help or info reguarding the issue.
God bless
Now that you know the truck and what has been done, tonight I pulled into the starbucks and I opened up my door and noticed the left side over head dome light was dimming and slightly blinking. I figured a bad connection so I popped it down for a second and went to tighten the little socket to see if it would be a quick fix. Well, that plan back fired and turned into a bad night. All of the sudden none of my accessories work!!!
Here is a list of the inop items:
[*]Air bag light is on[*]No power windows (can't roll them up, currently stuck down)[*]no garage door opener up in the visor[*]no dome lights[*]no radio[*]My "a/c" works... but the actual A/C part does not. I only get heat and the compressor does not kick on[*]no gauges (RPM, speed, fuel, temps, batt ect) although the lights in everything illuminates[*]no reading in my gauges with the miles, mpg ect... you know, the screen.
I checked the fuse box, switched around relays to see if anything changes, pulled out every fuse by hand to physically check them to see if they are bad one by one. Unplugged the battery for 10 minutes. Unplugged the computer in the engine bay also for alittle while... Im pulling up two codes: Fuel level sensor low voltage circuit, and OBD test incomplete or something like that.
I've also had a growing problem with if my door is open, I can not roll my windows up but I believe I know the issue for that from what I was reading about the wires getting chaffed in the door. but thats the least of my worries..
I hope I supplied enough info to bettery help with my diagnostics. I beg for any help or info reguarding the issue.
God bless
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swflkr (11-29-2012)
11-29-2012, 09:01 PM
#15
teh n00b
Thread Starter
Well some of my Friends hang out at the starbucks every once in a blue moon because its 24 hours and its a parking lot we can sit around and talk at without security or cops saying to find another place... lol
Anyone know much about the BCM's? So far other than the diode thats the only thing that makes sense, so I may purchase one if ford has it in stock. Are they interchangable? Will I have programming issues? odometer descrempsy issues? Anything that will be wrong when i plug in a new one or another one?
Anyone know much about the BCM's? So far other than the diode thats the only thing that makes sense, so I may purchase one if ford has it in stock. Are they interchangable? Will I have programming issues? odometer descrempsy issues? Anything that will be wrong when i plug in a new one or another one?
11-30-2012, 01:02 AM
#16
Senior Member
Hmm do you have access to a good digital multimeter? If you does it have a diode checking feature on it? If it does it will show one of two things while testing the diode, it can show an OL or open circuit meaning the diode is reversed biased, or it will show a 0.7V meaning the circuit is forward biased. However, if the diode is open then you will have a reading of OL on both side neither side will give you a reading. However if both sides give you a reading of .7V in either direction then the diode is shorted. Replacing this diode couldn't hurt, and I don't have access to wiring diagrams to know exactly what it does or where it goes. Otherwise I'm still thinking the BCM is at fault, but we really need you to check out more of the system before we can move on ya know?
11-30-2012, 01:06 AM
#17
Senior Member
Looks like that diode is the feed to the AC clutch, so that could be the issue with the AC Compressor not properly engaging mechanically, but explains why it will show up electrically.
11-30-2012, 01:11 AM
#18
Senior Member
Also to O.P. a BCM is nothing more than what you think it is, the Body Control Module. In this case though I believe Ford refers to it as the Body Security Module BSM, or the Vehicle Security Module VSM. They are all virtually the same thing just slightly different naming. This computer along with the other computers talk on a dedicated network known as CAN. This vehicle can contain a multitude of priority CAN networks setup as High Speed or Medium Speed CAN. Just know this if the BCM is starting to go then you can be looking at almost a grand to have it replaced. However, always check the easiest before doing anything else. Here are some fuses to double triple check for any issues.
#11, 13, 18, 27, 32, 107, and all of the relays as well. To check the relay just activate the circuit and make sure you hear an audible click when the coil activates and moves the spring. It's weird how computers work because they don't even have dedicated turn on wires, they use the CAN system to wake up and begin transmitting. Obviously each system and flavor of CAN can be different, but in the end it all works the same... remember digital is nothing more than 1s and 0s haha.
Last edited by BolletuH; 11-30-2012 at 01:18 AM.
11-30-2012, 08:32 AM
#19
teh n00b
Thread Starter
Bollet, when I was using a Fluke 87 when I was testing the diode. It was showing as an open circuit.
I will check those fuses again today and replace the diode. I would love to move on from the BCM but I really have no clue where to look. Im 90% sure all my fuses are good unless there are some somewhere else I don't know about along with my relays. As far as the wiring goes, I have no access to wiring diagrams right now so its hard to look up and see what goes where and start testing.
BCM's really over 1000? FML
I will check those fuses again today and replace the diode. I would love to move on from the BCM but I really have no clue where to look. Im 90% sure all my fuses are good unless there are some somewhere else I don't know about along with my relays. As far as the wiring goes, I have no access to wiring diagrams right now so its hard to look up and see what goes where and start testing.
BCM's really over 1000? FML
12-11-2012, 10:24 PM
#20
teh n00b
Thread Starter
Okay so turns out that there was a shorted wire up above my headliner that was shorting out against the body and that brought everything back to life. Then after that my door locks still weren't working so I replaced the body control module. Everything is now working EXCEPT my password entry thing on my door and my automatic headlight switch. I have to actually turn them on instead of automatically when it gets dark...
Any idears here?
Any idears here?
