NO power to radio, all fuses intact
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C32
NO power to radio, all fuses intact
Just like the title states. Shortly after I got a new battery, the radio wouldn't power on. I have checked all fuses, including the one behind the head unit. They are all good. I replaced a few with new ones just for good measure. Still no power to the head unit. Everything else is checking out ok. Please help.
Junior Member
Joined: Mar 2016
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From: tennessee
2006 C55 AMG
When i bought my car, there was no power to the radio. Looking through all the fuse locations, i narrowed it down to sound system. In my case the entire fuse was missing, not blown. When i put the fuse back in everything started working again just fine. If i remember correct its either 26 or 27 and its a 5 amp
Thread Starter
Junior Member
Joined: Jul 2017
Posts: 16
Likes: 0
C32
When i bought my car, there was no power to the radio. Looking through all the fuse locations, i narrowed it down to sound system. In my case the entire fuse was missing, not blown. When i put the fuse back in everything started working again just fine. If i remember correct its either 26 or 27 and its a 5 amp
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From: Chicago area
2015 E400 and 2015 GLK350
When you say that you checked the fuses, did you check them visually, or did you check them with an ohm meter or a continuity tester? Sometimes these fuses can look perfectly fine, but actually be blown. You can either check by pulling each fuse out and testing with meter or continuity tester (should light the light on continuity test or show zero ohms on an ohm meter), or you can use a volt meter and test to be sure you have normal voltage (if car is "off" should be 12 volts, if running, should be 13.6 volts or so) ON BOTH SIDES of each fuse. Sometimes power gets to the fuse, but not past it, indicating a bad fuse.
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Joined: Sep 2013
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'15 T&C & '14 SL63
sometimes there is a fusible link or inline fuse in the actual harness, particularly with high draw circuits like audio or lighting.
unfortunately its almost impossible to bench test anything anymore, so I would probably use a voltmeter to confirm I am getting +12v at the radio itself. You can use a needle to poke into the wire to get a reading. im sure many here will cringe at that thought, but i ask, what are the alternatives for trouble shooting?
unfortunately its almost impossible to bench test anything anymore, so I would probably use a voltmeter to confirm I am getting +12v at the radio itself. You can use a needle to poke into the wire to get a reading. im sure many here will cringe at that thought, but i ask, what are the alternatives for trouble shooting?
Thread Starter
Junior Member
Joined: Jul 2017
Posts: 16
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C32
When you say that you checked the fuses, did you check them visually, or did you check them with an ohm meter or a continuity tester? Sometimes these fuses can look perfectly fine, but actually be blown. You can either check by pulling each fuse out and testing with meter or continuity tester (should light the light on continuity test or show zero ohms on an ohm meter), or you can use a volt meter and test to be sure you have normal voltage (if car is "off" should be 12 volts, if running, should be 13.6 volts or so) ON BOTH SIDES of each fuse. Sometimes power gets to the fuse, but not past it, indicating a bad fuse.
sometimes there is a fusible link or inline fuse in the actual harness, particularly with high draw circuits like audio or lighting.
unfortunately its almost impossible to bench test anything anymore, so I would probably use a voltmeter to confirm I am getting +12v at the radio itself. You can use a needle to poke into the wire to get a reading. im sure many here will cringe at that thought, but i ask, what are the alternatives for trouble shooting?
unfortunately its almost impossible to bench test anything anymore, so I would probably use a voltmeter to confirm I am getting +12v at the radio itself. You can use a needle to poke into the wire to get a reading. im sure many here will cringe at that thought, but i ask, what are the alternatives for trouble shooting?
Thread Starter
Junior Member
Joined: Jul 2017
Posts: 16
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C32
MBWorld Fanatic!
Joined: Sep 2013
Posts: 1,185
Likes: 42
'15 T&C & '14 SL63
amazon (among others) has bladed fuse test lead sets. you can at least prove power coming into the fuse box (could be a blown larger block fuse at distribution panel for example).
GTC CT6100 Fuse Socket Connector Kit
Also, since does have a screw in fuse in the back, that makes a reasonable place to test power into the head unit w/o piercing a wire.
GTC CT6100 Fuse Socket Connector Kit
Also, since does have a screw in fuse in the back, that makes a reasonable place to test power into the head unit w/o piercing a wire.
Last edited by nycphotography; Oct 16, 2017 at 08:37 AM.
