running engine, wiring parking and tail lights
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From: Rotterdam
running engine, wiring parking and tail lights
1980 Oldsmobile Omega – Automatic Parking/Running Lights via Alternator Trigger
Today I wired the parking lights and tail lights so they automatically turn on when the engine is running, similar to how modern cars activate DRLs. I added an inline fuse and routed the lighting circuit through a relay.
The relay is triggered by the alternator output: when the engine starts and the alternator begins charging (around 13.8–14.4V), the relay engages and the lights switch on. With the engine off, voltage drops to battery level and the relay stays open, so the lights remain off.
This setup prevents any load on the original dashboard switchgear and keeps the system simple and reliable. Everything is fused, and the lighting circuit has its own dedicated fuse as well.
Works perfectly so far.
Today I wired the parking lights and tail lights so they automatically turn on when the engine is running, similar to how modern cars activate DRLs. I added an inline fuse and routed the lighting circuit through a relay.
The relay is triggered by the alternator output: when the engine starts and the alternator begins charging (around 13.8–14.4V), the relay engages and the lights switch on. With the engine off, voltage drops to battery level and the relay stays open, so the lights remain off.
This setup prevents any load on the original dashboard switchgear and keeps the system simple and reliable. Everything is fused, and the lighting circuit has its own dedicated fuse as well.
Works perfectly so far.
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