DRZ400E wiring problem!

[Chocolate Teapot]

Hello everyone, I am after bit of advice from anybody who knows more than me about motorbike electrics.

I have the below bike and the original rear light had smashed casings so I replaced it with an LED alternative.

The original light had 3 wires coming out, positive, negative and a switch

The new light has 3 wires, red, yellow & black.

I have tried numerous combinations and can only either get the running light to stay on or have a working brake light, never both!

The new light definitely has the functionality of a running light and a brake light as did the old tail light.

Has anyone got any suggestions?

Thanks

[Brite spark]

Black should be negative
Then it should just be a case of working out which of the red and yellow do the light or brake light

Connect it directly to the battery and see what happens, or if it even works.

[Chocolate Teapot]

I'm fairly sure the red is the brake light and the yellow is the tail light as direct power to each shows one dimmer than the other.

This is the issue really, I don't think the tail light has a switch if that's possible, not sure if there is any way to get around this

[bimsb6]

Chocolate Teapot said:

I'm fairly sure the red is the brake light and the yellow is the tail light as direct power to each shows one dimmer than the other.

This is the issue really, I don't think the tail light has a switch if that's possible, not sure if there is any way to get around this

It should be switched from the handlebars .

[Nickccc]

Which model and year is your bike? I have a DRZ and the Clymer book here with me, it has the wiring diagrams which I will post up for you.

[SherpaRob]

Black should be your earth, then the red should be the stop light connect that to what your calling switched and the yellow to the positive.

If the yellow is live when the ign is on or when the bike is running thats gonna be the tail light feed

the switched feed should be live when you activate the front or rear brake

And the negative is your earth as its an led rear light they are polarity sensitive

[Chocolate Teapot]

Cheers all, I should of said that I have tried every possible combination with the wiring other than feeding 2 into 1 if that makes sense, there has got to be something else that needs adding / changing.

There is no front brake switch either, purely a rear brake switch.

If I run the above combination of wires, neg to neg, power to running light, switch to brake light, the switch turns the light off if I remember correctly.

It's a DRZ400E 2000 model

[Ray Luxury-Yacht]

Bear in mind that 'LED' stands for 'Light Emitting Diode'... and the primary function of an electronic 'Diode' is to only allow power to flow one way through it.

For example - an ordinary Diode (not of the light-emitting type) is utilised in electronic devices, as a component that will not allow current to flow through it if exposed to it negatively - so if current is going one way through it, great, it lets it flow, but if the current reverses for some reason - the diode becomes like an 'off' switch and no power will flow through it.

LED's are exactly the same - despite emitting light when current flows through one way - if you reverse the polarity for whatever reason, then it won't allow it, and certainly won't glow or light up.

So an LED light unit MUST be wired up correctly - otherwise you won't get anything. A normal bulb doesn't care which way current flows through it - but an LED is one way only.

HTH.

[Chocolate Teapot]

Ray Luxury-Yacht said:

Bear in mind that 'LED' stands for 'Light Emitting Diode'... and the primary function of an electronic 'Diode' is to only allow power to flow one way through it.

For example - an ordinary Diode (not of the light-emitting type) is utilised in electronic devices, as a component that will not allow current to flow through it if exposed to it negatively - so if current is going one way through it, great, it lets it flow, but if the current reverses for some reason - the diode becomes like an 'off' switch and no power will flow through it.

LED's are exactly the same - despite emitting light when current flows through one way - if you reverse the polarity for whatever reason, then it won't allow it, and certainly won't glow or light up.

So an LED light unit MUST be wired up correctly - otherwise you won't get anything. A normal bulb doesn't care which way current flows through it - but an LED is one way only.

HTH.

This makes sense as to why the normal bulb works as I would expect and why the LED doesn't.

However, I'm still really struggling to find the correct way to wire it

Determined not to have to give it to an auto electrician to sort unless I absolutely have to!

[Hooli]

Got a voltmeter I'd be using a diode tester on it to work out which two wires make which circuit.

[Ray Luxury-Yacht]

Chocolate Teapot said:

Ray Luxury-Yacht said:

Bear in mind that 'LED' stands for 'Light Emitting Diode'... and the primary function of an electronic 'Diode' is to only allow power to flow one way through it.

For example - an ordinary Diode (not of the light-emitting type) is utilised in electronic devices, as a component that will not allow current to flow through it if exposed to it negatively - so if current is going one way through it, great, it lets it flow, but if the current reverses for some reason - the diode becomes like an 'off' switch and no power will flow through it.

LED's are exactly the same - despite emitting light when current flows through one way - if you reverse the polarity for whatever reason, then it won't allow it, and certainly won't glow or light up.

So an LED light unit MUST be wired up correctly - otherwise you won't get anything. A normal bulb doesn't care which way current flows through it - but an LED is one way only.

HTH.

This makes sense as to why the normal bulb works as I would expect and why the LED doesn't.

However, I'm still really struggling to find the correct way to wire it

Determined not to have to give it to an auto electrician to sort unless I absolutely have to!

Ok, two further thoughts...

First, post a picture of the unit up on here showing the wires, that would help.

Second - there is a possibility that the unit is dead out of the box. It wouldn't be the first time I've bought a brand new part and it doesn't work...especially if it's made in China, as most of these LED light units are..!

[Chocolate Teapot]

Ray Luxury-Yacht said:

Ok, two further thoughts...

First, post a picture of the unit up on here showing the wires, that would help.

Second - there is a possibility that the unit is dead out of the box. It wouldn't be the first time I've bought a brand new part and it doesn't work...especially if it's made in China, as most of these LED light units are..!

Cheers

I will try and get some pictures tomorrow, I can't see it being dead as the correct functionality does work, just not together!

[Nickccc]

That's odd as the diagram for the E model only shows two wires going into the rear light,


Here's the S and SM diagram.


If they aren't clear enough mail me with an address and I will mail them to you.

[Nickccc]

Just having a dig around, the 400E doesn't have a rear brake light or indicators.
Only the S and SM models do unless it's been retro fitted.

[Chocolate Teapot]

Thanks, I can see them

I think the original E model must of came without a working brake light?

perhaps why mine is only switched from the rear brake

[Chocolate Teapot]

this is the combination to have a working brake light

Yellow (running light) to white (neutral)
Black (negative) to green/white (switch)
Red (brake) to brown (power)

To have a working tail light but not brake the combination is

Brown (power) to yellow (running light)
Black (negative) to white (negative)

Switch doesn't make a difference on this except cut the light off when brake is pressed.