04 Cayenne Turbo System error: Amplifier not available

[ChinchiChiang]

Hi guys,

Recently my 04 CTT with factory BOSE system developed an weird problem. When the car is cold and/or outside temperature is below 50 degree F, when first start the car, PCM would give me "System error: Amplifier not available." It sometimes happened sometime in January, and it happens more frequent now. I did some research on it, and some says it's battery, some says PCM, and some said bad Amplifier. I thought it was the battery, because the car did have a slow cranking, so I replaced it with a new Porsche DEKA battery several weeks ago. However, the problem is still there. I reset the PCM several times (BTW, it's version 3.0) and it didn't get ride of the problem. So, I am in the processing to get a replacement amplifier.

It appears that my Amplifier is made in 2002 with part number AMP,4166 MOST, E1 PROD and 7L5.035.456B.

According to some internet sources, it should be compatible with 7L5.035.456F and 7L5.035.456D.

I want to replace it with the most recent one so it will last longer for my investment, and I see the 07/08 Cayenne Turbo models came with AMP,411 MOST, E1 PROD and 7L5.035.456G that are dated 07/08. Will the G model work?

Another question is that my local dealer said the amp I have is for CDR 23, but the Cayenne came with a PCM, and it has been working fine for the last couple years. I don't think the CDR 23 model could work with the BOSE version, was the information he gave incorrect?

Porshe PN is 955-645-901-04

Thanks in advance.

Edited April 7, 2014 by ChinchiChiang

[hahnmgh63]

Could be the amplifier but sometimes a problem with the MOST fiber optic bus will give those errors. Check the connection. It should be the plug with the two Orange wires going into it.

[sydneyca]

Had a similar problem on my 04 S with same system..took it to another dealer and he was able to fix by changing the CD changer ..

[ChinchiChiang]

Thanks for the suggestions.

1. I did check the connector before, and it was tight. Furthermore, a lose connector will have the symptom happen randomly, not just when weather is cold or system not warmed up right?

2. PCM is outputting the amplifier code, I know the CD changer is right under it, but I really don't think it's the CD changer. I could be wrong, but the system should still output sound without the CD changer connected.

I purchased a 7L5.035.456G which is dated 06 from ebay and the system accepts it and outputs sound fine. My assumption is that as long as it matches AMP,4166 MOST, E1 PROD, it is interchangeable with all 03-08 Cayenne equipped with PCM and BOSE system.