Electrical Issue: No lights, locks or start but airbag light illuminates

[E36X5er]

Went to start my 2004 4.4 three days ago - pressed unlock, lights flashed as normal. Interior lights were on as normal when I opened the door. Put the key in the ignition and as it began to turn over, everything went out, all lights etc… Took the key out and and tried again but it was dead. No lights, no clicks, nothing. I heard a sound when everything went out that made me think it was a short of some kind.

When I put the key in the ignition and turn it, nothing happens besides the airbag light illuminating.

Recent work done - new battery (1 month), replaced alternator with a Bosch unit (1 month)(DIY). Truck has an after market ignition after I had major issues with the factory ignition after ordering a replacement key.

Any idea if this is a fuse or relay? Door locks, hazard lights, interior and exterior lights, ignition have all stopped working

[andrewwynn]

Check the battery connection and voltage at the battery. You'll have to use the emergency release to open the trunk


–awr–

Using Tapatalk VIP on iPhone

[EODguy]

The hot (+) wire to the starter and check the "b" terminal under the hood...

Sent from Embassy network using Tapatalk

[andrewwynn]

I thought of that at first but that only affects starter and alternator. Everything else goes though a separate feed down the starboard side. Fed from a master block in front of the tire/air compressor.

The weird part is airbag light lit means some power but i don't think e53 has any memory battery like some newer models have so no idea how that will light if no interior lights and no dash lights.

That said it feels like a major failure of a battery connector or main power block.

The pyro fuse is only on the start cable so that everything else still runs.

Have to take a look and see/DMM the battery bay


–awr–

Using Tapatalk VIP on iPhone

[E36X5er]

Ok so I finally got around to looking at this - took the battery out and charged it fully again (brand new battery) and when I put it back in, the car started right up. Went to menu 9 and the voltage while off was 12.4 which make sense bc it just came off the charger.

the behavior was weird when it died, which brought me to post here, bc it was sudden - almost like a fuse blew and everything shut off.

now im curious if I have a parasitic drain going somewhere - I installed a new alternator (DIY) and a new battery. any tips on looking for an electrical drain?

I'll check tomorrow morning to see what the battery level is at

[andrewwynn]

Certain parasitic drains will kill the battery overnight. Have you looked into yet? The ac blower motor FSU is the most common cause but telematic unit is the second most.

When the "hedgehog" fails it will prevent sleep. You can confirm sleep when the light on the gear shifter goes out.


–awr–

Using Tapatalk VIP on iPhone

[E36X5er]

Originally Posted by andrewwynn

Certain parasitic drains will kill the battery overnight. Have you looked into yet? The ac blower motor FSU is the most common cause but telematic unit is the second most.

When the "hedgehog" fails it will prevent sleep. You can confirm sleep when the light on the gear shifter goes out.


–awr–

Using Tapatalk VIP on iPhone

Interesting - ever since Ive had the truck, the AC hasn't worked - always blows warm air - not sure if that's a freon leak or something else. Something Ive always noticed is that the shifter light never turns off.

I took the X5 up the coast for a weekend (200 miles round trip), this was about 8 days ago. After that trip it sat for 6 days or so; battery level this morning, on the hidden menu, was 11.9V but it started fine.

I tried to connect my charger to the terminals in the front to charge it a little and the charger just says "put clamps on" - its a viking charger.

[andrewwynn]

Unplug the hedgehog and see if the light turns off.


–awr–

Using Tapatalk VIP on iPhone

[X5chemist]

Time to do a parasitic draw test on the GMIII module. It took me 6 months to find a draw. A replacement cloned GMIII module fixed the no sleep problem. My X5 sleeps at 11 mA.

[paramax55]

When the car is running, you should have a minimum of 13.4V on the battery. I like 14, but it shortens the life of the battery. If you don't have more than 13V, the battery isn't charging.