I N S TA L L AT I O N   I N S T R U C T I O N S
AXSUB-CH8
AxxessInterfaces.com  © COPYRIGHT 2024 METRA ELECTRONICS CORPORATION  REV. 2/2/24 AXSUB-CH8
• AXSUB-CH8 interface
• AXDSPX-CH8 vehicle T-harness (LD-DSP-CH8) 
• Bass knob (LD-BASSKNOB)
ATTENTION: With the key out of the ignition, 
disconnect the negative battery terminal before 
installing this product. nsure that all installation 
connections, especially the air bag indicator 
lights, are plugged in before reconnecting 
the battery or cycling the ignition to test this 
product.
NOTE: Refer also to the instructions included 
with the aftermarket radio.
TOOLS REQUIRED
TABLE OF CONTENTS
Connections.................................................................2
Programming..............................................................3
Testing..........................................................................3
Specifications...............................................................3
Troubleshooting..........................................................4
• Crimping tool and connectors, or solder gun, 
  solder, and heat shrink • Tape • Wire cutter
• Zip ties • Multimeter
INTERFACE FEATURES
CHRYSLER (Add a SUB) Interface 
2021-UP
Visit AxxessInterfaces.com for more detailed informaon  
about the product and up-to-date vehicle specic applicaons
INTERFACE COMPONENTS
• 
Can be used in amplified and non-amplified models
• Easy behind the radio installation with pre-wired harness
• Bass knob included for level control of subwoofer amp
• Micro-B USB updatable
www.AxxessInterfaces.com
www.MetraOnline.com
MetraOnline.com may be used to assist 
with dash assembly instructions. Simply 
enter your Year, Make, Model vehicle 
into the vehicle fit guide and look for 
the Dash Kit Installation Instructions.
If the vehicle is equipped with Active noise 
cancelation (ANC) microphones, they will 
need to be bypassed. Please refer to www.
Axxessinterfaces.com for ANC bypass 
harnesses offered for select vehicles.