Most likely it should work if installed correctly.. The factory setup, assuming yours was factory and not modified/tampered with by previous owners, should be a connect and play.
The factory setup is pretty basic 20-40 watt system, with 4 ohm speakers. does the new unit have any setting or switchest o change output for 4/8 ohm outputs.
If you already have it installed, you or someone either used a harness/adapter orcut and spliced wires. If wires are spliced I'd check all the connections where the splicing was done.
The adapter referenced above would be like below, made to allow a new radio/headunit to be installed without cutting factory wire harness.. solder is best connection, but connect color coded wires to new radio and plug into factory wire harness.
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