Son's LR3 has all of a sudden (a little over a week now) is experiencing vehicle not starting and tons of lights:

Here is symptoms he is experiencing.
Vehicle will not start. Jump boxing it will not immediately get it started. After about 20 minutes of sitting it will start.

Other symptoms:TPMS no power ( I guessing the light is coming on)

Audio headunit no power. Vehicle fault, system "shutting down” on the head unit display

Cruise hold works but Cruise Control (speed change) doesn't do anything, after getting it started and moving of course)

Emergency blinker button, no power

Windows, powered

Turn signal not working

Wipers don’t work

Ac no power

When car turned off while in this failure state, it wouldn’t turn back on immediately. Turned on again after waiting 20 min

Battery seems healthy according to a multimeter and tested OK by the local parts dealer. (which doesn't mean much if there is a ground issue)

Seems intermittent, but only when driving. Could not replicate at idle.

Potentially related to a right rear brake light that wasn’t operating properly (not illuminated when headlights were on).

Those are the list of items he gave me.

I had him do a hard reset, but issue comes back.

Bad Battery (even though it tested ok)?

Not getting a good ground on the battery terminal? He states he has it tight and it will not slip on the terminal.

I'm flying out to Fort Carson this week and plan on troubleshooting and hopefully fixing the issue. I have some coolant things I am going to fix for him as well.

Any thoughts?

 

Def try another battery. But I have seen issues with the main fuse. Its a large 400amp (I think 400) located on the positive post, sides on the side of the battery when things are all mounted up nice. People have found corrosion there and those large fuses can crack/fail so they are worth swapping. And they are cheap. Then I would move onto the main ground lead and another one is inside the passenger wheel well area, inboard but I forget if its on the frame or body panel - prob body. But it is a known PITA one.

 

It seems that the main headlight connector to the H7 bulb was brittle and some melting had occurred. It literally fell apart in my hand when trying to unplug.

I’ve disconnected it, taped off the exposed connectors, and unplugged the light housing.

the U0167 symptoms have not occurred sense.

sourcing a new connector to put everything together and test.



Question, how would this have flipped out the MOST system therefore causing all this havoc?

A short would have just simply blown a fuse. Is it possible that the ground flopping around could have screwed with the MOST system?

 

That was not on my bingo card. No clue how it would have affected other systems like that, very weird....

 

Well, That DID NOT fix it.

Once I got a H7 connector, zipped everything back up, the symptom came back.

I unplugged the front light assembly, and the U0167 code and symptoms went away.

Tomorrow, I will simply unplug the H7 bulb but plug the assembly back in with everything else working. Hope that works. If not, I will get a whole either new or known working assembly and see if that keeps the U0167 code and symptoms from coming back.

Stay tuned.

 

Well, it seems the headlight assembly issue didn't turn out to be the culprit. I chased some coincidences which turned into a rabbit hole.

Got everything together and when it happened again, I banged on the cluster a few times and it would go away. Maybe more coincidences.

Battery and Alternator are somewhat new, had AutoZone check anyway and they said all checked out. Took my trusted Fluke and my readings seem to confirm that.

Tomorrow going to get me some harbor freight jack stands, and dig my way to the grounding behind the right front tire. Between WP, stationed in Germany and now Colorado, it maybe corroded good.

Standby yet again.

 

Have you checked/replaced the main fuse yet?

This s**t is frustrating! I know it. But I am still leaning to a mains power issue. Grounds, positive cable, etc. And never, ever rule out the battery - I dont care how much it is tested. One bad cell can do some really weird ****, learned that with my BMW. So dont rule it out because I would hate for something simple (swapping a battery is not hard) to bit ya in the butt.

 

I did remove the air box and battery to inspect everything I could on top,. The 2 50amp FL17 & FL18 fuses looked good and had no corrosion. I even put leads into them and smacked around a bit to see if something was going on inside of them.

I've got and have had Bimmers as well. Love them, but also a love hate relationship. My M (knock on wood) hasn't given me any issues yet.

I cleaned up (they were not bad) the ground connections under the air box. The Power and Ground leads from the battery look perfect on the top side. Reinstalled everything and tightened up the battery leads good and heavy snugged. Tomorrow going to lift, remove the tire and fender well stuff to inspect, clean, and re-tighten the ground there and inspect the power cable to the alternator.

After that, I can replace the battery and inspect the Cluster for a loose cable, cracked solder joints, etc. At my age, my soldering capabilities are not what they used to be

Wish me luck!

 

Talking about this fuse. I have seen LR3 that, for some reason, do not have it. It it generally up against the battery since the positive post is integrated. I know of at least once instance where the fuse was bad but tested with a meter okay - just could not handle the amps. And a couple cases of corrosion.

 

Chassis ground LR3
Is this the Chassis ground I should be worried about? Doesn’t look very corroded but gonna clean it up any way.

if this doesn’t fix the issue , going after the FL block Dakota posted above and/or the battery.

then if none of that fixes the issue going after connectivity of the cluster.