Amplifier and Navigation "not found"
01-26-2022, 03:02 PM
#16
Ok, if this car came into the shop that I work at, I would do the following.
Perform MOST diagnostic ring test with PIWIS tester when fault is present (cold ambient temp). The results of this test should tell me what control unit (PCM, NAV, SAT, AMP, CD etc.) is causing the BUS to fail. The control unit in question will either be electrically or optically faulty. We have a fiber optic "jumper" plug that we plug in, in place of the suspect faulty control unit. If the system comes back to life and operates as designed with the jumper installed, then bingo, you verfiyed the problem. Replace that item. Do not throw parts at this problem
, it is a very easy system to diagnos for Qualified techniticians. Sounds like the Amp is bad, they have been known to fail. Like I said, it would take 10min. for a good tech to veryify this with the PIWIS tester when the problem is present. Feel free to PM me for more MOST system details.
Perform MOST diagnostic ring test with PIWIS tester when fault is present (cold ambient temp). The results of this test should tell me what control unit (PCM, NAV, SAT, AMP, CD etc.) is causing the BUS to fail. The control unit in question will either be electrically or optically faulty. We have a fiber optic "jumper" plug that we plug in, in place of the suspect faulty control unit. If the system comes back to life and operates as designed with the jumper installed, then bingo, you verfiyed the problem. Replace that item. Do not throw parts at this problem
, it is a very easy system to diagnos for Qualified techniticians. Sounds like the Amp is bad, they have been known to fail. Like I said, it would take 10min. for a good tech to veryify this with the PIWIS tester when the problem is present. Feel free to PM me for more MOST system details.
01-27-2022, 11:11 AM
#18
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when this happens it is usually a failure in a device on the MOST optical loop. each device on the loop receives and transmits optical pulses that form a data stream, therefore any device failing on that loop can break the loop and nothing works. In my car the telephone module under the seat had got wet and I had no sound - the pcm said no amp, no cd chager and no phone. The easiest way to isolate units is to get a pair of bypass connectors off ebay or similar and swap out each piece until it bursts in to life. The sat nav cd / dvd seems to be a common fault but the phone module would be the forst one I would go for. The amp is a mare to get at so I would eliminate the others first.
01-29-2022, 02:10 PM
#19
when this happens it is usually a failure in a device on the MOST optical loop. each device on the loop receives and transmits optical pulses that form a data stream, therefore any device failing on that loop can break the loop and nothing works. In my car the telephone module under the seat had got wet and I had no sound - the pcm said no amp, no cd chager and no phone. The easiest way to isolate units is to get a pair of bypass connectors off ebay or similar and swap out each piece until it bursts in to life. The sat nav cd / dvd seems to be a common fault but the phone module would be the forst one I would go for. The amp is a mare to get at so I would eliminate the others first.
01-29-2022, 02:36 PM
#20
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my car is a UK spec one, it is under the driver's seat, which is the passenger seat on lhd cars. Wind the seaat all the way forward and fully up - the phone module is the flat silver box - mine had a Motorola sticker on it. The connector that looks like it has 2 orange wires is the MOST connector - this is the one you need to bypass.
01-29-2022, 03:13 PM
#21
my car is a UK spec one, it is under the driver's seat, which is the passenger seat on lhd cars. Wind the seaat all the way forward and fully up - the phone module is the flat silver box - mine had a Motorola sticker on it. The connector that looks like it has 2 orange wires is the MOST connector - this is the one you need to bypass.
