METRA
METRA 701786 Amp Integration Harness car electronics accessory
Connects an aftermarket radio to the factory harness in 1991-1999 Mercedes and 1999-2004 Land Rover Discovery models while retaining the original amplifier via RCA inputs
- TypeCar Stereo Add-Ons
- ColorBlack
- Retains factory amplifier with low-level RCA inputs
- Plugs directly into OEM radio harness for plug-and-play fit
- Pre-stripped wire ends enable quick, secure connections
- OEM-quality ABS connectors ensure reliable terminal contact
- Compatible with Land Rover Discovery 1999-2004 and Mercedes 1991-1999
Amp Integration Harness for Land Rover and Mercedes
The Metra 701786 harness lets installers connect an aftermarket head unit to the factory wiring in Land Rover Discovery 1999-2004 and Mercedes 1991-1999 models. It retains the OEM amplifier and provides low-level RCA inputs for a clean signal path. Pre-stripped leads and EIA colour coding make the splice-to-harness step straightforward. OEM-quality terminals and ABS moulded connectors deliver a secure, plug-in fit.
Thermals noise and power draw in normal use
As a passive wiring harness the unit generates no heat, produces no audible noise and adds no measurable load to the vehicle 12 volt system. Current flow is limited to the signal and remote-turn-on circuits already present in the factory amplifier wiring. The reversed constant and accessory wires on this part number simply match the vehicle pin-out without changing power consumption.
Upgrade from speaker-level adapter or direct splice
Replaces improvised speaker-wire-to-RCA converters or hand-soldered taps that can introduce noise and reliability issues. The factory-matched connectors and RCA plugs eliminate guesswork when keeping the original amplifier. Installers who need a second amplifier channel or a full bypass of the OEM amp will require a different harness topology.
Highlights
- Retains factory amplifier with low-level RCA inputs
- Plugs directly into OEM radio harness for plug-and-play fit
- Pre-stripped wire ends enable quick, secure connections
- OEM-quality ABS connectors ensure reliable terminal contact
- Compatible with Land Rover Discovery 1999-2004 and Mercedes 1991-1999
Specifications
| Brand | Metra |
|---|---|
| Type | Car Stereo Add-Ons |
| Color | Black |
Questions about this item
How do I install the Metra 701786 harness and keep the 12 V constant and accessory wires from being reversed?
Plug the harness directly into the vehicle’s OEM radio connector; the wires follow the EIA colour code, but the 12 V constant and accessory wires are swapped compared with the 70-1784 version, so match each wire to the aftermarket radio’s harness by colour rather than position.
What part of the Metra 701786 harness will need replacement if the RCA plugs or pre-stripped ends wear out?
The harness is a single moulded assembly with OEM-quality terminals and pre-stripped ends; if the RCA plugs or wire ends fail, the entire harness must be replaced.
Which vehicle models limit the use of the Metra 701786 harness under sustained operation?
The harness is designed only for Land Rover Discovery 1999-2004 and Mercedes 1991-1999 models; using it outside those applications is not supported.
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