Tacoma 2017 audio question

Hi, I have a 2017 tacoma that I'm adding a 4 channel amp too.

I'm trying to wire channel 1 and 2 to the front speakers by tapping into the existing speaker wire from the back on the stock headunit.

I'm running wire from channels 1 and 2 from the amp and tapping into the door speakers from behind the headunit but it isn't working. No sound is coming out. What I'm i doing wrong?

Basically I'm trying to amp the door speakers by t-tapping into the existing stock speaker wire from behind the headunit.

I've noticed the door speaker wiring is a different color than the image below. Example front right door is blue/grey for pos and negative when you take off the door panel and look at the wiring.

But behind the headunit the same door is violet/red for positive and violet/green for negative.

Help would be awesome.

I'm using this:

 

If that is your amp, you are using RCA’s correct? So your hi low level adapter should have the speaker wires from the headunit to the hi lo adapter, then RCA’s out to the amp input. Amp output should be spliced to the speaker wire that was cut and ran to the hi lo adapter. You didn’t mention if you had an aftermarket headunit so I’m assuming you are using the stock one.

Is the amp turning on? Check to make sure the crossover settings are on HPF or full.

Also that is a nice amp, you should really consider upgrading your stock speakers. Oem speakers aren’t going to handle the power you will be feeding them with that amp.

 

You will need to clarify this because it really sounds like you literally connected amplifier outs via T-Taps to the speaker wiring from the back of your factory radio without interrupting the circuit and using the radio’s speaker outs as inputs to the amplifier.