Gremlins!!!!!

[mmeade]

Hey everyone...long time quiet member, rare poster because I simply am still learning a lot from you guys!

So here is my current electrical gremlin story. Yesterday everything seemed happy in Explorer land, 2007 4.0 V6 with 95k on the clock and my daily driver. This morning I went to turn it over, got a "whir" sound and then nothing! Interior lights wouldn't even go on. Jumped it easily off my wife's vehicle and let it run for awhile. Airbag warning light was on, and every now and then the parking brake light and brake system warning light would come on but then turn back off. I drove it about 20 mins, turned off, and then went to turn it back on...again, nothing! Got a jump, same story, took it to the local autozone and got...novice..advice. They tried to sell me a new alternator until I insisted we try a new battery first (current battery was 4 years old and voltage was less then 2 after being driven around). So great, new battery is in, they ran their test of my alternator throught the battery saying it was putting out 14.6 volts but failed 1 of the 3 tests and that it would "die anytime now" I decided to take my life into my hands and wait it out. So not my Explorer starts right up, idles fine, go to turn on the manual HVAC...nothing..go to shift from park with my foot on the brake, button will not depress. Fuse number 20 on the interior box (Manual climate, DEATC, Brake shift) is blown. Shut down my vehicle. Replaced the 10 amp fuse, start it up, blows right away. Decide to try a little troubleshooting, disconnect the power supply to the blower motor which is so mercifully easily located under the passenger side dash. New fuse..blows! So here I am, no warning lights, self-test shows charging system OK. But no heat in the Pennsylvania late fall and using the manual override to shift. HELP!!!
No idea what DEATC is for the record, and I replaced the shift lock interface earlier this year (PIA).
Thanks for reading my novel..and help would be appreciated!

 

[mmeade]

Ok..figured out DEATC is dual electronic automatic temp control which I do not have. So I guess I can eliminate that as a cause...I checked all my fuses and number 20 is the only one that is blown

 

[mmeade]

Would a problem with the blower motor relay cause the fuse to blow?

 

[Flag Gibby]

You clearly have a short in that circuit somewhere. Since you recently replaced the shift interlock interface, I would start by checking those wires to make sure that the shielding is still in place and no wires are exposed. There is no way that the blower motor resistor could be causing the issue since the fuse still blew with the power pulled and there is no power draw from it in the off position.

 

[mmeade]

Awesome..was planning on digging in there tomorrow..thanks for the advice

 

[mmeade]

So some digging today proved fruitful. The shift interlock module appears to have gone rogue. With all three plugs removed, I am able to put a fuse in without it blowing, and have functioning heat! Plugging the power supply and interface plug back into the rear of the module makes the fuse blow regardless of whether or not the brake pedal sensor and lock selonoid plug are inserted or not! So a new module is ordered and hopefully Monday I can free myself of this gremlin. Till then I have a running driving car with heat by utilizing the shift lock override.
And for anyone who need to replace their shift lock module, this is the 2nd time I've done it, and I shaved 2 hours off my time by simply removing the passenger seat to improve my access to shifter area!

 

[mmeade]

For resolution...I replaced the shift interlock board and everything is back to normal. Not sure at which point in the process the board got fried, whether it was when the autostore tried to jump it, or charge the battery, or switch out the battery, or test the alternator...but it's fixed!

 

[fbopretired]

was wondering how the passenger seat removal gave better access to replace the shift interlock module

 

[fbopretired]

Is there another way to change out the shift interlock module without seat removal. I tried to unplug the 3 wires from the module yesterday but could only reach 1 of the 3 plugs.

 

[mmeade]

I've done it both with seat removal and without, and without you spend a lot of time with skinny tools trying to unclip and clip in the harnesses..in the end I saved a ton of time just removing the seat..removing the seat and sliding the center console back out of the way gives you easy access to the module

 

[fbopretired]

floor shifter

thanks for the reply about the shift interlock replacement. on my 06 explorer, I can shift out of park, but it may take 4 0r five attempts before the shifter disengages. Does that sound like the module or possibly a different component.

 

[mmeade]

Yeah that sounds exactly like the shift interlock...I've done it three times now, and here is how to get it done, open the center console and undo the screws under the front, pull up from the rear on the center console cover, the shifter plastic chrome ring will pop off. Disconnect the aux and 12 volt connectors, remove the passenger seat by popping the covers off and using an impact driver to back out the bolts, remove the center console front kick plate covers by popping out the retaining pins, then on either side of the console there are grey screws, there are 4 screws in the console (2 towards the front, 2 towards the back) unscrew them, disconnect the large electric connector that powers the rear 12 volt, Etc...the pull the center console to the rear of the vehicle and that should make easy access to the white cover over the interlock board. Undo the 3 connectors, switch it out, reverse the process and you're done. I may have missed a screw or two since I'm typing this out of memory..but good luck!

 

[fbopretired]

Thanks!

Yeah that sounds exactly like the shift interlock...I've done it three times now, and here is how to get it done, open the center console and undo the screws under the front, pull up from the rear on the center console cover, the shifter plastic chrome ring will pop off. Disconnect the aux and 12 volt connectors, remove the passenger seat by popping the covers off and using an impact driver to back out the bolts, remove the center console front kick plate covers by popping out the retaining pins, then on either side of the console there are grey screws, there are 4 screws in the console (2 towards the front, 2 towards the back) unscrew them, disconnect the large electric connector that powers the rear 12 volt, Etc...the pull the center console to the rear of the vehicle and that should make easy access to the white cover over the interlock board. Undo the 3 connectors, switch it out, reverse the process and you're done. I may have missed a screw or two since I'm typing this out of memory..but good luck!

Thanks so much for providing the details for this repair. I really appreciate it!

 

[mmeade]

if you don't mind, maybe post pictures while you do it to pay it forward for the next guy..thanks

 

[fbopretired]

Worked Well

Well, thanks to your suggestion, I was able to replace the shift module. I did remove the screws holding the console in place and slid the unit back as you said. This gave easy access to the module. I didn't have to remove the seats to get to the 4 side bolts. I moved the seat forward for access to the rear 2 and back to access the front two bolts. The new module fixed the shift problem. Unfortunately, I had the job done before I read your suggestion about picture's. Next time for sure! Thanks again.