Does 1999 Lexus LS 400 Require Powered 4-Pole Wiring Harness
Question:
Since led use so little energy can I just tap into my cars tail lights,turn signals and stop wires or do I need to buy a powered light converter that runs the wire to the battery. 99 Lexus ls400 is the car Im thinking of connecting the lights to.
asked by: Mike
Expert Reply:
You are correct that LED lights use only a fraction of the power needed by standard incandescent light bulbs. They also last longer than bulbs, they do not tend to turn yellow-ish in color with age like bulbs do and they generate less waste heat.
Despite these worthwhile attributes you do still need to use a powered converter on your Lexus in order to connect LED lights for the various light functions like stop, turn and tail light signals.
The main benefit of using a powered converter type wiring harness is isolation. The powered harness module provides protection for your car's own internal wiring in the event of a short-circuit or overload. Replacing the harness would be relatively painless as compared to having to do repairs on the vehicle's OEM wiring. Call it cheap insurance that is well worth the price.
The three 4-pole wiring harness options for your 1999 Lexus LS 400 are shown on the linked page. All share identical installation processes so no one kit is easier than another. Out of all options I suggest the kit # C59496 because we have found their wiring products to be very reliable. A helpful installation article is linked for you.

Products Referenced in This Question
Curt Powered Tail Light Converter w/ 4-Way Flat Trailer Connector and Install Kit
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Vehicle End Connector
- Powered Converter
- Universal Fit
- 4 Flat
- Plug and Lead
- Splice-In
- CURT
more information >
Product Page this Question was Asked From
Curt Powered Tail Light Converter with 4-Pole Flat Trailer Connector
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Vehicle End Connector
- Powered Converter
- Universal Fit
- 4 Flat
- Plug and Lead
- Splice-In
- CURT
more information >
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