CurtPalme.com Home Theater Forum

**Curt Palme** · Posted: Fri Oct 15, 2010 3:50 pm Post subject: Mystery Marquee 8500- dead

I sold a refurb 8500 to a customer back in January I think. It worked for a month, then came up with an H fail that a new CLM and H deflection board didn't cure, so I sent him another set that I retubed and ran the heck out of. It worked for about a month, then died as well.

From what I remember, the LVPS failure light came on, so I sent down another one. Now the standby light is on, it appears that the CLM is getting data from the wired remote, but the set will not turn on. I've sent a number of boards down, fully tested, to no avail. As per his last email this morning:

I've now tried all three CLM boards and no change in status - rear red LED flashes once on pushing POWER once (wired remote only), delay required to get that LED to flash again. The red LED on the remote flashes with each push of any button.

I've also confirmed no other projector LEDs (exc the amber) light or flash regardless of remote output. And I've confirmed the red LEDs on the LVPS are not lit and do not flash.

Back in September, I told him to pull all connectors and boards save for the LVPS and CLM to see if the belly fans will kick in. He's about to try it again.

This is an 8500, so I can't see it being glycol leakage on the backplane.

Any other ideas that I'm missing?

thanks!

Tim in Phoenix · Joined: 21 Oct 2006 Posts: 4409 Location: Phoenix

Were any of the projectors or CLMs set to Protocol B? Were keys pressed to lock out that projector address 000 ?

**Curt Palme** · Posted: Fri Oct 15, 2010 4:10 pm Post subject:

I don't think so. I thought of the protocol thing this morning. Is the protocol stored on the backplane or the CLM?

Tim in Phoenix · Joined: 21 Oct 2006 Posts: 4409 Location: Phoenix

Weak batteries in the IR remote could be an issue also.

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**Curt Palme** · Posted: Fri Oct 15, 2010 5:00 pm Post subject:

He's using the wired remote..

Tim in Phoenix · Joined: 21 Oct 2006 Posts: 4409 Location: Phoenix

Some Marquees were built with the wired keypad cable (and IR sensor cable) tie-wrapped too snug against a sheet metal edge next to the red tube. Over time, the sheet metal begins to cut into the cables and could short them out. It make be worth looking at. Also, the wired keypad may have issues.

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draganm · Joined: 08 Mar 2006 Posts: 8990 Location: Colorado

**Curt Palme** · Posted: Fri Oct 15, 2010 7:11 pm Post subject:

I retubed this machine, and I always wire tie the remote and IR cables up so that doesn't happen. My thought is that perhaps there's some short in the set that is causing the LVPS to shut down completely, and not pulse like it normally does? Was thinking maybe the plastic sheet between the back heatsink and the ribbon cables has slipped?

garyfritz · Joined: 08 Apr 2006 Posts: 12088 Location: Fort Collins, CO

Two 8500's failing in a short time seems very suspicious. Could noise, brownouts, or spikes on the power line cause these failures?

Tim in Phoenix · Joined: 21 Oct 2006 Posts: 4409 Location: Phoenix

draganm · Joined: 08 Mar 2006 Posts: 8990 Location: Colorado

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

Isn't that memory chip on the backplane board part of the control system? If it fails, could it cause start-up problems?

Strange problem. I've never heard of a Marquee having so much replaced and still not turning on.

I'd definitely want to take a spare CLM and put it in another machine and verify that it is properly configured to default settings.

If someone got into the wrong (factory) service menu, they could make the unit unable to start up if they made the wrong software value changes.

CJ

**Curt Palme** · Posted: Sat Oct 16, 2010 1:02 am Post subject:

That's why I posted, either it's a really long run of bad luck, perhaps there's an AC power issue, or I'm missing something. I was hoping for the third...

**Curt Palme** · Posted: Thu Dec 02, 2010 9:41 pm Post subject:

OK, I finally got this on the bench.

Problem 1- dead wired remote. The light was flashing, no action on the CLM. Jumper wires on the remote were in the right place. Haven't tried it in wireless mode yet. So I connected a new hardwired remote. THe set turned on. THen it turned off about 5 seconds later, with an LVPS fail light.

I proceeded to disconnect/unplug the HDM/VIM/focus/neck boards/CCM/heat sink and it would still shut down. Pulled the CLM, reseated the chips. Still shut down.

I then swapped out wired keypads, and a couple of confirmed working ones wouldn't power the set up at all. I started chasing a whole pile of stuff, then realized that I only had 4.3 volts on the power supply line for the keypad. It's supposed to be 12 volts. It comes from the standby 12 volt supply (which was at a solid 12 volts, loops through the CLM, then comes out on the backplane. I swapped CLMs, still at 4.3 volts.

I then temporarily set up another backplane and motherboard carefully floating on top of the Marquee chassis, (tubes removed), and put in a CLM so I could measure the 12 volt supply at the keypad connector. I got a solid 12 volts.

So the problem with this set is a bad backplane. I'm about to spend 90 minutes swapping it out, as I'm determined to find out where my 12 volts is disappearing. Corrosion maybe? Bad feedthrough point on the multilayer board?

Tim in Phoenix · Joined: 21 Oct 2006 Posts: 4409 Location: Phoenix

Hey!

Possible shorted wired keypad cable, possible shorted IR sensor, possible loose contacts in the lvps bulkhead connector.

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Tim in Phoenix · Joined: 21 Oct 2006 Posts: 4409 Location: Phoenix

Hey!

Possible shorted wired keypad cable, possible shorted IR sensor, possible loose contacts in the lvps bulkhead connector. Possible chewed wire harness that drooped into the core fans.

Any lvps or other leds lit?

.

draganm · Joined: 08 Mar 2006 Posts: 8990 Location: Colorado

**Curt Palme** · Posted: Thu Dec 02, 2010 11:35 pm Post subject:

OK, the backplane is out, and it turned out that water or glycol got under the CLM connector. It corroded underneath the 64 pin connector. I don't get how stuff got under it. The rest of the set is clean other than the dust on the fans. No signs of glycol leakage anywhere, but I guess if this happened a long time ago, the glycol got cleaned up by a tech save for under those contacts.

Anyways, problem found, that's the main thing.

Dragan, this is the first set from that customer, he still has the H fail one. I'm taking the tubes out of this set and will put them in another chassis to ship down.

draganm · Joined: 08 Mar 2006 Posts: 8990 Location: Colorado

**Curt Palme** · Posted: Fri Dec 03, 2010 1:34 am Post subject:

I'm pretty sure they did all come from the same place. Ran into another strange problem with the same set, although I was testing H boards in it, so it's unrelated to the first problem:

Have a forum member that wants a quad decoder for a Marquee. Since I've finally got a MArquee on the bench, I fired in a quad decoder, and got an H fail. At 480i with 4 different quad decoders, I got an H fail. So I finally figured it wasn't the quad decoder. Smile

Turned out it's the main board of the HDM. I did also notice a slight foldover on the left side on 480p and above, so I'm suspecting a main issue on the HDM. So.. a strange MArquee day. I'll post pix of the corrosion under the 64 pin chip in a bit..