4x4 + Brake + ABS lights + sluggishness...then "clunk" and Trans Safe Mode Program

[Porschesolutions]

Went out of town & left the X5 with the misses, she picks me up an hour ago and it's sluggish, heavy-feeling, and those lights are on.

Have plenty of PS fluid and the serpentine belt is on, so we drove home. A block from the house while lightly cruising downhill at 40mph, I hear a clunk in the drive train and the "Trans Safe Mode Program" flashes up on the dash for 10-20 seconds & then goes out.

Crap, what's up with all this?

yes, it could be alternator/battery, but not the clunk and Trans mode flash right?

Mark
'06, 103k miles 4.8is

[bcredliner]

X5 electronics are very sensitive to voltage changes. When the charging system is faulty the dash can light up with a variety of problem messages. How old is your battery?

[upallnight]

Sluggishness could be attributed to the ABS kicking in. The DSC also controls the trans so whatever is causing the trifecta of lights to appears you need to get that resolved.

[Porschesolutions]

Ok so I read quite a few posts last night from this forum and eventually went back outside to check a few things:

12.2v on the battery as it was (100d outside, about 2hrs after last drive)
13.4v at the jumper post (+) and strut stud adjacent to it (-) when running.
I found an OBC diagnostic thread and found 13.4-6v at idle/revving through the OBC.
I then reset the whole OBC to see if that would do anything. No.

This am, battery was fully charged per my smart charger, started her up, still getting the 4x4, ABS, and Brake lights but the sluggishness is gone: steering feel was back to normal, transmission shifts smoothly through all gears, etc.

Drove into town & got a Starbucks. Back in the truck, no lights are on now & things are peachy. Dropped the wife off at her office and drove to mine: everything's fine.

I think it all started with the 4x4 light coming on once/twice last week & that led to a snowballing of events. Still doesn't explain the "clunk" I felt a nanosecond before the Trans Fail Safe Program flashed on my dash...but if the 4x4 sensor(s) are going that could lead to a wierd setting/shift/power transfer that caused that clunk.

Any input is appreciated. For now I'll look into the "4x4" indicator and what that is & what sensors control that.

Mark

[Porschesolutions]

Ok so I read quite a few posts last night from this forum and eventually went back outside to check a few things:

12.2v on the battery as it was (100d outside, about 2hrs after last drive)
13.4v at the jumper post (+) and strut stud adjacent to it (-) when running.
I found an OBC diagnostic thread and found 13.4-6v at idle/revving through the OBC.
I then reset the whole OBC to see if that would do anything. No.

This am, battery was fully charged per my smart charger, started her up, still getting the 4x4, ABS, and Brake lights but the sluggishness is gone: steering feel was back to normal, transmission shifts smoothly through all gears, etc.

Drove into town & got a Starbucks. Back in the truck, no lights are on now & things are peachy. Dropped the wife off at her office and drove to mine: everything's fine.

I think it all started with the 4x4 light coming on once/twice last week & that led to a snowballing of events. Still doesn't explain the "clunk" I felt a nanosecond before the Trans Fail Safe Program flashed on my dash...but if the 4x4 sensor(s) are going that could lead to a wierd setting/shift/power transfer that caused that clunk.

Any input is appreciated. For now I'll look into the "4x4" indicator and what that is & what sensors control that.

Mark

[xRide]

When this happened to me, I changed my alternator/voltage regulator and it's been 2 weeks and no problems so far. Some say the voltage isnt being regulated properly and that is the problem. And some the the alternator is going bad. To avoid testing both units, I purchased the alternator, which has the voltage regulator built into it and changed it.

BTW, This is a 4.8is...year 2005 with now 60k miles.

[Porschesolutions]

My alt should be good, it appears the regulators are iffy: where does one purchase just the regulator??

Am I correct that our alternators are water-cooled as insinuated on other threads?

Mark

[upallnight]

Instead of throwing parts at it get the truck scan. Even though the lights has gone away, not every DTC triggers a light. You could have pending code(s).

[Porschesolutions]

From this forum it appears that theres not a code for voltage spikes...just syptoms and remedies per replacing the alternator/regulator. Am I incorrect? Having codes read in the am.
Mark

[xRide]

Also, another thing that was happening was that my nav screen and radio went in and out. Now my nav screen has pixilation in it....and its getting worse.