# Radio/amp issue



## newellbaxter (9 mo ago)

2016 Nissan Sentra sound cutting out every 2 mins. Voltage drop at stock amp but no drop at radio. Any help would by appreciated


----------



## VStar650CL (Nov 12, 2020)

If it has an amp then I presume the system is Navi-with-Bose. The Navi and Bose Amp have completely different power supplies. The fuses for the Bose (two 15A's in parallel) are in the Fuse & Fusible Link Box under the hood. The wires go from the Engine Room Harness to the Main Harness through a big SMJ connector (E4 to M2) and then to the Body Harness on a smaller 10-position connector (M7 to B2). Both connectors are under the kick panel next to the driver's left foot. They're both susceptible to water damage, so if the car has a sunroof make sure the drains aren't overflowing onto the connectors. I've attached the AV section of the FSM for you:


----------



## newellbaxter (9 mo ago)

To add to 1st post the wire I tested was the amp on wire. Also the radio doesn't power off just the sound


----------



## VStar650CL (Nov 12, 2020)

newellbaxter said:


> To add to 1st post the wire I tested was the amp on wire. Also the radio doesn't power off just the sound


The amp-on signal is pulled-up inside the Bose and you often won't see full battery voltage on the line. The main thing is seeing solid ground when the signal transitions low, any meaningful voltage means there's resistance in the connection or a weak transistor in the head unit. If you're not getting any sound check the power circuit, the parallel fuses often behave just like the parallel fuses on blower motors. I.e., one gets weak and blows for whatever reason, then the other can't support the amp and blows too. If you're getting sound momentarily but it quits, check all your speakers for a short or low coil resistance.


----------



## newellbaxter (9 mo ago)

so I tried unplugging the amp but have same issue every 2 mins sound off then on and also Bluetooth off then on. I also checked and cleaned the connectors under kick panel. Can't located the chassis ground for the system. Help


----------



## VStar650CL (Nov 12, 2020)

Sound cutting in and out almost always means a shorted coil in one of the speakers that's drawing too much current and overheating the amp. Ohm your speakers, you'll probably find one that reads much lower than its rating. Or try disconnecting them one at a time and see if the in-and-out behavior stops. If the speakers all read healthy then ohm the speaker wires to each other and to ground with both ends disconnected, any reading besides infinity will mean a wiring problem.


----------

