Yup i posted on those forums. You are right about testing on known working vehicle. Doubtful i will find somone willing to test the monitor but gps def possibility. I will keep looking hopefully I can find someone. Would be a shame to waste more money without knowing for sure.

OK - Update... Kind of Good News:

Spoke with Alpine Electronics of America in Allendale, NJ today. They told me that as long as my screen is not completely dead they will repair the unit for $150 and warranty the repair for 90-days. Even if a PCB needs to be replaced. I just need to pay shipping to them. They can ususally fix them withing 24 hours but have a 5-7 business day turnaround. If nothing is wrong with the unit they will send me the unit back without cashing the check (Thanks for the offer tho UCrewX5!!!)

The guy mentioned they are repairing one unit right now that has the same problem. I have no other way of testing the monitor so I will probably just send it in this week.

I am still trying to find someone with a X5 or M5 that will let me test the GPS units, tho they are probably fine. I am scouring the other boards trying to find someone. Which models came with nav? All of them?

So worst case scenario I should have a fully functional 2006 model DVD GPS System for less than $900 total and I should be able to sell the old CD GPS unit on eBay.

I suppose it's possible the monitor is fine and i may lose the money shpping the monitor to Alpine, but it really seems like its the culprit. I just wish I had a way to to tell for sure. If GPS units test out fine then I will pretty much be convinced. I suppose its possible the wiring harness could still be bad but this seems highly unlikely.

I think I finally found a local that will help me test the GPS units!!!! Thanks to bimmerforums! The test vehicle is a 7/1999 production 740. I'm guessing MKII/4x3 like my X5 (was). If these babies boot up I will be pretty confident that its the monitor and I should be good to go for hopefully <$200.

Actually at least 1 more 7-series person has stepped forward now :) They have 16:9/MK4 and the old 4x3 and MK2!!!! Perfect! Now I can test both my GPS units AND verify my wiring on my X5 so I should be able to tell exactly whats up.

I'm really surprised, that nobody knows the problem of the white screen.
I have 16:9 units for X5 and also for E38/E39. They are different. The monitor part has a different part no. and the casette unit has also different part no. in case of E39 and X5.
E39
monitor: 65 52 6 934 415 (old partno.:65 52 6 913 385)
unit: 65 52 6 928 389
X5
monitor: 65 52 6 934 416 (old partno.:65 52 6 915 517)
unit:65 52 6 988 771

If you mix the units (eg. E39 unit with X5 monitor), you will get white screen. I don't know the exact reason, but I had the white screen problem 2 times, and both were because of mixing the units.
Check the part numbers. The monitor's parts number is on the back side, so you have to push the eject button to check it.

Bombolo

This unit supposedly came from a 2006 X5, part #'s

65-52-6 980 246 & 65.52-6 988 771 (little sticker) on metal top cover
65-52-6 934 416 on back of screen.

Thanks to Nathan @ Babbitt Motor Werks in Mesa, AZ my NAV system has finally been diagnosed. It is my screen as suspected. Both my MK2 and MK4 worked in my X5 with a spare 4:3 screen he had laying around, we also tried the units in a 740 and they worked there as well. I would certainly reccomend this shop to others in the Phoenix/Mesa/Tempe/Scottsdale area.

Shipping my unit to Alpine in NJ with a check for $150 in the morning.

Got my screen back today $150 for the repair and $12 shipping via USPS. I think they overcharged me by $25 but I am just happy the damn thing finally works!

Glad you are fixed now. I have used both types of wide screen monitors in my e38 and never had a white screen there. I am currently using an X5 unit.

Part #: 6590 6 969 263-01
Manufacture Date: 12-05
HW:1.0/SW:6.0