MACH audio issues

[jlo82585]

hey y'all, so I recently purchased an 02 expedition E.B. with the mach audio system. my issue is the sub doesnt work and the sound out of the other speakers doesnt sound very clean or loud. I have heard from many people the AMP's are prone to failure so I removed mine and opened it up but I dont see anything visibly damaged and there is not burnt odor in the amp at all. Is there any other tests I can run to ensure the amp is my issue?

 

[splintrcel]

Look at the transistors pressed up against the metal amp casing. These are the most common point of failure for an amp. I had mine go out as well and bought a used one off of ebay for like $90. As for the poor speaker quality, there is a change there are loose connectors behind the head unit so pull out the radio and check them out. Also throw in a cd and see if the sound is better because the rear integrated antenna could be damaged or the fender mounted standard antenna thus affecting the radio function of the head unit.

 

[bedrck46]

http://www.expeditionforum.com/f45/mach-audio-issues-23257/#post188780

 

[murmaider2]

Look at the transistors pressed up against the metal amp casing. These are the most common point of failure for an amp. I had mine go out as well and bought a used one off of ebay for like $90. As for the poor speaker quality, there is a change there are loose connectors behind the head unit so pull out the radio and check them out. Also throw in a cd and see if the sound is better because the rear integrated antenna could be damaged or the fender mounted standard antenna thus affecting the radio function of the head unit.

I've had the same problem as you've mentioned and many of these tips worked. I took out the amp, found a blown transistor. Ended up getting an amp out of a 98 lincoln town car, and I caked the transistors in the "new" amp with CPU thermal paste for better heat dissipation into the casing of the amp. For the poor sound quality, open up the passengers side trunk window and peel away the headliner where it opens, there is a connector up there that goes to the window integrated antennae, make sure that connection is tight. Also the poor sound quality could be caused by blown out speakers, the previous owner of my expy probably blasted the radio which might have contributed to the blown sub amp and ruined speakers. I replaced all 4 doors with JBL GTO series speakers, and now everything sounds amazing.

 

[willbill92]

I am having issues with my 02 EB Expy and my speakers all work fine minus the subwoofer what are some troubleshooting steps to do. I cant seem to find a new amp anywhere.

 

[murmaider2]

I am having issues with my 02 EB Expy and my speakers all work fine minus the subwoofer what are some troubleshooting steps to do. I cant seem to find a new amp anywhere.

Get behind the passengers side panel inside the trunk (this requires removing any trim that is around this one huge panel and the seatbelts for the 2nd and 3rd row). Unplug the subwoofer from the amplifier, stick the prongs of a multimeter inside the connector and see that the subwoofer reads 4 ohms, if it does then the speaker is fine, if it doesn't then its blown. Otherwise the amp is toast. I'm going to upgrade both my sub and the amplifier this weekend, I'm going to have a functioning speaker and amp, if you need either or both, let me know.