Bosch Relay

[razor]

I want to install some aux. back-up lights on my truck using a relay that taps into the trucks back-up lights. I have an old Bosch 5 prong relay from an old fog light set which I lost the instructions for. Here what I have.

1 red wire with in-line fuse
1 yellow with female connector
1 blue wire
2 black

I figured the red is to the battery or fuse panel.
Yellow to one terminal of the switch.

Would the 2 black wires go to each aux lamps and the blue to the trucks's back-up lights? If this is the case would the other terminal on the switch go to ground?

Thanks

[wyldman]

If it's a Bosch relay,it should have the terminals marked on the bottom with numbers.

85 and 86 are the primary coil.You'll need to power one and ground the other to energize the relay.

The hot wire (fused) from the battery goes to terminal 30.

87 is the output terminal.Some relays will have two 87 terminals (normally open),which are both hot with the relay energized.Some other relays will have an 87A terminal,which is normally closed,and hot with the relay de-energized.This type of relay switched power from the 87A to the 87 terminal when actuated.

So to simplify,this is how you hook it up.

85 - tap into truck reverse lamps
86 - good ground
30 - battery power (fused)
87 - aux lamp(s)

[wyldman]

Should have posted this in the first place.This is Alan's wiring diagram from Chuck's site.

It shows how to wire it up with a SPDT switch,so you can have the aux lights on by themselves,on with the truck reverse lights,or not on at any time.

It's a little more work,but gives you full control of the lights at all times.Nice if you have someone tailgating you. :cool:

[wyldman]

Forgot the attachment. :rolleyes:

[razor]

Thanks Chris

Those # are on the relay, it makes sense to me now.

Ray