Just hoping someone here can help me out.
My PCM 91 is displaying a message E4 upon startup and will go no further.
Does anyone know what this message means.
I have consulted the manual and tried contacting Lexicon to no avail.
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Lexicon PCM 91 Error
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The manual is somewhat ambiguous about this. Error E4 is described as the error code that occurs when the unit fails the Display Test which is part of the power up diagnostics. However, the resulting Hex Error Code that is loaded in the Error Log is described as occurring when "No RAM size information available" That is, you might have a memory chip failure. However, the power up diagnostics start the memory tests after the first 4 tests have completed. Which would tend to indicate that it's not a memory failure. All a bit confusing.
When you power up the machine and get the error display, take a look and check whether the 0dB headroom LED is lit. If so, note down which of the 6, 2, 18 & 24 LEDs are lit or unlit and let me know.
When you power up the machine and get the error display, take a look and check whether the 0dB headroom LED is lit. If so, note down which of the 6, 2, 18 & 24 LEDs are lit or unlit and let me know.
- Howard Jones
- TRM Endorsed

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- Location: Sydney
[quote="Howard Jones"]The manual is somewhat ambiguous about this. Error E4 is described as the error code that occurs when the unit fails the Display Test which is part of the power up diagnostics. However, the resulting Hex Error Code that is loaded in the Error Log is described as occurring when "No RAM size information available" That is, you might have a memory chip failure. However, the power up diagnostics start the memory tests after the first 4 tests have completed. Which would tend to indicate that it's not a memory failure. All a bit confusing.
When you power up the machine and get the error display, take a look and check whether the 0dB headroom LED is lit. If so, note down which of the 6, 2, 18 & 24 LEDs are lit or unlit and let me know.[/quote]
Hi Howard, well it's been a little while but the problem has re-surfaced and I have taken note of which LED's were lit. the Red 0db and the 24 LED are both lit. I hit the LOAD button and continued through it's startup procedure but at the end showed message DIAGNOSTIC FAILURE.
Does that help diagnose the problem?
It eventualy booted up again succesfuly after a few minuits wait.
When you power up the machine and get the error display, take a look and check whether the 0dB headroom LED is lit. If so, note down which of the 6, 2, 18 & 24 LEDs are lit or unlit and let me know.[/quote]
Hi Howard, well it's been a little while but the problem has re-surfaced and I have taken note of which LED's were lit. the Red 0db and the 24 LED are both lit. I hit the LOAD button and continued through it's startup procedure but at the end showed message DIAGNOSTIC FAILURE.
Does that help diagnose the problem?
It eventualy booted up again succesfuly after a few minuits wait.
-

David W - Regular Contributor

- Posts: 268
- Joined: Sat May 07, 2005 8:08 pm
- Location: Wagga Wagga NSW
David W wrote:TimS wrote:David,
Was that the one on Ebay recently for a dirt cheap price because of the error??
Tim..
No.
Was just wondering - there was one on Ebay recently for like 200+US bucks that had the same error - the seller actually stated that he could not get it fixed..
-

TimS - Valued Contributor

- Posts: 1734
- Joined: Tue May 15, 2007 3:11 pm
- Location: Sydney
Just thought I'd give an update on this as it seems I'm not the only one to encounter this problem.
I called Jands about a month or so ago as they were recomended as the Lexicon repaires. When discussing this problem with them they had two possible solutions. One being a reset which I didn't try and the other removing the two large memory chips and re seating as the connections can get corroded.
Anyway I have tried this and seems to be working relyably so far.
I called Jands about a month or so ago as they were recomended as the Lexicon repaires. When discussing this problem with them they had two possible solutions. One being a reset which I didn't try and the other removing the two large memory chips and re seating as the connections can get corroded.
Anyway I have tried this and seems to be working relyably so far.
-

David W - Regular Contributor

- Posts: 268
- Joined: Sat May 07, 2005 8:08 pm
- Location: Wagga Wagga NSW
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