Need help troubleshooting wifi/bluetooth on iMac G4

davidg4781

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Oct 28, 2006
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Alice, TX
I had previously had problems with my wifi. It would have to be in the same room as the router to connect. Anywhere else in my small apartment wouldn't work.

I recently tried using a Microsoft Bluetooth Mouse and a Mighty Mouse with no luck. I have to keep it within like 3" of it for it to stay connected. If I move it back any further it loses connection.

I had been a bit reluctant to open it up completely since I didn't have any thermal paste but I have some and I'm about to order a new internal battery so I'm ready to open it up. Does anyone have any ideas of what to look for? Since I have to mess with the thermal paste I'd rather not open it up unnecessarily. I will say I haven't really messed with thermal paste so it may not be as much hassle as I think it is.

There performance is pretty good when you stay off the web and I'd like to keep this just because it's awesome. I was planning on getting an internal 1GB RAM module but would rather not invest much more money into it until I can sort out the wifi/bluetooth issue.

Oh, and with my 2010 MBP, wifi and bluetooth work wonderfully and just as expected so I'm pretty certain the problem is with the iMac.
 

davidg4781

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Original poster
Oct 28, 2006
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Alice, TX
I think I may have found the issue. I opened up the iMac and found a loose wire, and I'm pretty sure it's either to the wifi or bluetooth. Any help?
 

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DeltaMac

macrumors G3
Jul 30, 2003
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I suspect that your bluetooth antenna is not seated completely, or is simply disconnected, because it does work at very close distance, so the antenna is a likely fix.
Two connections to check: the antenna where it connects to the bluetooth board, and the tiny single-wire connector, probably in about the same location as the same connector for the Airport antenna wire. You have to completely pull out the logic board to check the bluetooth antenna connector, and you can check the (wifi and bluetooth) extension connections at the time you pull open the bottom case. While you have it all opened up, you would reseat the bluetooth board in its logic board connector, too.
Not an easy task, but if you want to check the antenna connectors, that's what you will need to do.
The thermal paste is not terribly difficult, unless the case has NEVER been taken apart. Separating the heat sink is tricky then. If you have the Apple service manual for your iMac G4, that would be the time to review it.

Saw your picture. Looks like a wire that has been crushed/broken, probably was jammed into the edge of the case when it was last closed up. Can't say for sure, but it is likely why your bluetooth has no distance. There's another wire that's just behind that piece, which looks like the very similar airport antenna connector. They just come apart with a gentle tug. If the piece that is in the foreground has the same one-wire connector, then you need to find the OTHER part that's broken. You will likely find that if you REMOVE the logic board, and follow to the bluetooth board. It's visible through the plastic on the BOTTOM side of the logic board, near the Airport card. You can see it, but it's only accessible by removing the logic board.
Splice that wire, and you should be good to go with bluetooth.
(You may need to replace the heat PAD on the bottom side of your logic board. I'm not sure what you would use for a substitute for the pads.
 
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davidg4781

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Oct 28, 2006
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Alice, TX
I do not have a repair manual. I tried taking the Logic Board out and it won't budge near the connectors.

By the way, do you know how to get this connector off? I can't tell if it pops off or if the wires come out. Neither one are moving any, but I don't want to put too much pressure on them.
 

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Intell

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Jan 24, 2010
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You have to remove the iMac's logicboard to remove that antenna wire. It connects to either the Bluetooth board or the Airport Extreme card under the logicboard.
 

DeltaMac

macrumors G3
Jul 30, 2003
9,535
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I do not have a repair manual. I tried taking the Logic Board out and it won't budge near the connectors.

By the way, do you know how to get this connector off? I can't tell if it pops off or if the wires come out. Neither one are moving any, but I don't want to put too much pressure on them.
That connector has a cover that you have to remove. See where the cover flares out where it touches the board? It's held in place by double-sided tape, so pry under the edge - one side, then the other side. (good place to use a plastic "spudger" :D ) Alternate back and forth, and you will loosen that cover. You can completely remove the cover, I think. The connector then simply comes loose, IIRC.
When you reassemble, the adhesive has probably hardened and won't stick. Easy to replace that with a small bit of similar double-side sticky tape.

Important that connector is seated properly when you reassemble. It's the main video connector.

There's 4 screws to remove, and one is plastic!
Grab the logic board by the battery retainer and the hard drive connector. Lift the board slightly and pull back to release the board from the bottom housing and I/O ports. Note: The I/O port covers may come out with the logic board when it’s removed. Just put those back in place when you reassemble.
 
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davidg4781

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Original poster
Oct 28, 2006
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Alice, TX
Frustrating.

Sorry, no pics. iCloud is taking ages to send it from my phone to my MBP and Tapatalk signed me out of MR... and I forgot my password.

So I removed the logic board. Bluetooth antenna is broken. Looks like it had been pinched and broke apart previously. The wifi antenna looks like it had been pinched as well. I'm guessing both need to be replaced.

They have a connector that goes to the top of the case and it appears past these connectors everything is in great shape. I don't know if this had been opened in the past before I got it or not. It was pretty clean inside not counting a few dust bunnies.

So, now what do I repair this with? I'm assuming I'll be able to find these antenna wires somewhere online. Is it worth doing anything else while I'm inside? Maybe upgrade the BT card or anything like that?

----------

Ridiculous. $1050 for a replacement logic board. Why not just buy a new iMac? I get the fun of PowerPC but not for that price.

Anyway, looks like powerbookmedic.com is going to be the best place, at least online. Anyone have any other sites to look at?
 

fhall1

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Dec 18, 2007
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(Central) NY State of mind
Ridiculous. $1050 for a replacement logic board. Why not just buy a new iMac? I get the fun of PowerPC but not for that price.

Anyway, looks like powerbookmedic.com is going to be the best place, at least online. Anyone have any other sites to look at?
That is ridiculous - seeing as how you can get an entire working iMac G4 on ebay for somewhere around $100.
 

Intell

macrumors P6
Jan 24, 2010
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The antenna wire for the Bluetooth use standard connectors on the ends. You just have to fin one that has the same connectors on both ends.
 

davidg4781

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Original poster
Oct 28, 2006
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Alice, TX
Alright, so I contacted a few local Apple repair places and some national websites. No one seems to have the two extensions I need, but they have some for the older models. One place told me that they are not compatible. I'll look for the BT one... maybe I can find something online that will work, such as what Intell said.

I'm thinking, for now, the best thing to do is put it all back together and do without Airport and Bluetooth. I'm going to go ahead and replace the PRAM battery. Is there anything else I should do? I have new thermal paste but I do not have thermal pads. Can I just buy these at Altex or do they need to be iMac G4 specific?

I may pull out the HDD and ODD to clean out that part of the iMac.
 

Intell

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Jan 24, 2010
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The thermal pads on the underside of the logicboard? Those typically don't need to be replaced unless they are dried out, cut, or very worn. They can be reused.
 

davidg4781

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Oct 28, 2006
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Alice, TX
The thermal pads on the underside of the logicboard? Those typically don't need to be replaced unless they are dried out, cut, or very worn. They can be reused.
Great. Mine look to be in really good condition. I think I'm going to upgrade the HDD... OWC has a 250GB IDE WD 7200 drive for $40, down from $80. Checking with Newegg that seems like too good of a deal to pass up.

By the way, here are the pics I tried uploading the other day. Extension wires completely toasted. Too bad they are so hard to find.
 

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Intell

macrumors P6
Jan 24, 2010
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I'll look around the internet for a compatible connector later today. Do you need the one with the male or female connector on the extension wire? Do you need one for both Airport and Bluetooth or just Bluetooth?
 

davidg4781

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Oct 28, 2006
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Alice, TX
That'd be awesome, thanks!

I need the extensions for both, going from the boards to the connector that goes to the display.

The wifi cable going from the APE card has a female end. The bluetooth connector has a male end.

Edit: I did a quick search. I was able to find the wifi online, the bluetooth one seems to be one that's hard to find.
 

davidg4781

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Oct 28, 2006
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Alice, TX
Just an update. I pulled the drive carrier out. It's not that dirty inside but there's a bunch of dust under this copper tape. I'm pretty sure it was opened previously, maybe to clean it out, the put back together.
 

Intell

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Jan 24, 2010
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The thing you need is a MHF to MCX extension wire. The MHF end is the male end for the dome and the MCX end is the female end for the Bluetooth card. You need one that is about a foot long. It can be longer, but not too much longer as it has to be coiled up inside the dome.
 

davidg4781

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Original poster
Oct 28, 2006
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Alice, TX
The thing you need is a MHF to MCX extension wire. The MHF end is the male end for the dome and the MCX end is the female end for the Bluetooth card. You need one that is about a foot long. It can be longer, but not too much longer as it has to be coiled up inside the dome.
Do you have any specific sites to check other than google? I've been searching all day and can't seem to find anything really quick.

I did find the Apple part on macpalace.com... It was going to be about $50 shipped. Ouch!
 

Intell

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Jan 24, 2010
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I haven't been able to find one of those cables after a quick search. Also note that they only came in G4 iMac's that came with the optional Bluetooth built in. They were not standard in G4 iMacs like the Airport antenna.
 

davidg4781

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Original poster
Oct 28, 2006
2,238
174
Alice, TX
I haven't been able to find one of those cables after a quick search. Also note that they only came in G4 iMac's that came with the optional Bluetooth built in. They were not standard in G4 iMacs like the Airport antenna.
I was hoping they came with the add on card which would maybe mean there's more in wild. There's a local place that said they don't have it in stock but can get me one for $25, no warranty. I'd guess as long as it's not physically damaged there's a pretty good chance it'll work.

The service manual says to use Kapton tape to hold everything down. It's a bit expensive and I really don't think I'd need this for anything else, is there anything else I can maybe use?
 

Intell

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Jan 24, 2010
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The antennas are supposed to go into the little black clasp on the drive tray. The Bluetooth boards in G4 iMacs were not a user upgradable part. Because of this, they had to be ordered by an Apple tech as a package of the Bluetooth board and the antenna. The Bluetooth board used in G4 iMacs is the same part number as used in non-PCI-e PowerMac G5's, eMac's, and some iMac G5 models. But the iMac's had a separate part number for the Bluetooth antenna cable. Have you thought about removing the internal Bluetooth and using a USB solution?
 

davidg4781

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Original poster
Oct 28, 2006
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Alice, TX
The antennas are supposed to go into the little black clasp on the drive tray. The Bluetooth boards in G4 iMacs were not a user upgradable part. Because of this, they had to be ordered by an Apple tech as a package of the Bluetooth board and the antenna. The Bluetooth board used in G4 iMacs is the same part number as used in non-PCI-e PowerMac G5's, eMac's, and some iMac G5 models. But the iMac's had a separate part number for the Bluetooth antenna cable. Have you thought about removing the internal Bluetooth and using a USB solution?
I really don't need Bluetooth on it at all. I just wanted to keep it as original and fully loaded as possible. I was hoping to find one while working on the other issues to put it all back together.

I thought of skipping on wifi too but that's more necessary, I think. Right now it's connected via ethernet but if I ever move anything to a different room I'll need the wifi. I could get a bridge and connect it via ethernet I guess. I've already ordered the wifi extension.

I'm actually not sure if keeping that on the network since it's G would slow the network from N to G. In reality it doesn't matter much at this point.
 

Intell

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Jan 24, 2010
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If the wireless network has more than one broadcasting antenna and MIMO support on the router, the whole network does not slow to G or B speeds if a slower or older device connects to it. That was only true for devices that did not support MIMO across multiple antennas. Most wireless routers sold since 2007 have the needed support.
 

davidg4781

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Oct 28, 2006
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Alice, TX
What happens if I purchase something like this?

I'm guessing it won't work since that cable will basically be inside the faraday cage. I think the one that's built in routes it to the display area for maximum coverage.