New Topics › Forums › General Discussion › 1999 – 2002 Nissan Quest › Replacement Sub-Woofer for '99 Quest With Premium Sound › Reply To: RE: No Bass
If you have no bass but you still have sound, then you are likely to have a premium sound system and your sub-woofer is suspect. There are no relays in the sound system by the way.
The amplifier in the sub is a small metalic box attached to the composite box that holds the sub-wofer. The amplifier receives power-on (terminal 3 on sub-amplifier) and sound signals (terminals 1, 2, and 4) from the main radio receiver system. The sub-woofer amplifier has a 20A fuse (No.11, located in the fuse box) that goes to sub-woofer amplifier terminal 6. The sub-woofer has an amplifier that might be bad or the sub itself might be culprit. All above is assuming you still have the factory audio unit.
If you have an after market radio unit, then it is very likely the sub-woofer was not connected. You need to make the new connections using the pre-amp RCA type connectors on the back of the sound system and the power-on signal to turn on the sub-amplifier. You will also need a small sub-harness if you don’t want to start cutting wires.