Headlight Circuit Modification Gives Better Lts & No Dim Dip

[Penelope Stopit]

Disconnect and remove Dim Dip Control Unit ECU

Disconnect and remove Dim Dip Unit ECU



Join Red/Yellow to Blue/Red @ Dim Dip Control Unit ECU Plug



Dim Dip Is No Longer

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If required

Improve headlight voltage supplies

Fit, fuse and wire 1 x Dip Beam Relay and 1 x Main Beam Relay at a chosen place within the front interior of the vehicle

Use Main Beam LH cable and Dip Beam RH/LH cable shown in the above diagram to activate the Dip and Main relays

Run new up-rated cables from relays to light units

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For the more adventurous

Remove all rear lighting ECUs and build a complete new circuit as shown below



A small modification to the rear fog and side/tail light circuits is required, see below diagram and information

Edited by Penelope Stopit on Monday 13th December 08:02

[magpies]

Hi Penny - I know it isn't a Cerb but on my S I've just started (tonight) to pull all the original wiring harness apart and remove the unused / unwanted wiring.

I have removed the dashboard and most of the wiring is now laying on tyhe floor.

Already quite a number of redundant wires removed including the useles Dim Dip.

I am willing to listen to ways to improve the electrical system (I even may incorporatesome too )

[tofts]

Got to say, Im pretty good with wiring and actually don't know what is your trying to achieve, at least by means of several different types of relays and what appears to be an additional fuse holder?

EDIT:
A recent edit to original post now has the answer!

Edited by tofts on Monday 26th November 12:00

[Flatplane8]

I don't know if this helps, but I did this in a different way. I took the TVR headlight and fan plugs at the front of the car and used them to switch relays (with the relays switching heavier cable direct from the battery to the lights and fans). Thus the TVR wiring is only switching the relays on/off, with the power coming via a feed with less voltage drop. Also did this on the 3000M I had before and it helps to improve the brightness of the lights.

[Penelope Stopit]

Flatplane8 said:

I don't know if this helps.......

Your method will help many

The above diagram is more for those that have faulty control units or wish to bin the lot and start again

Purely out of interest, did you have a problem with the dim dip circuit holding the dip beam relay in?

[gruffalo]

Flatplane8 said:

I don't know if this helps, but I did this in a different way. I took the TVR headlight and fan plugs at the front of the car and used them to switch relays (with the relays switching heavier cable direct from the battery to the lights and fans). Thus the TVR wiring is only switching the relays on/off, with the power coming via a feed with less voltage drop. Also did this on the 3000M I had before and it helps to improve the brightness of the lights.

This is what I have also done on my car.

It keeps the control units as normal but relieves them of any load, has worked faultlessly for 10 years or more. I am thinking of one further modification and that is to tidy up the inline fuses and mount a small fuse board somewhere under the bonnet to make a neater job of it all.

[CerbWill]

gruffalo said:

This is what I have also done on my car.

It keeps the control units as normal but relieves them of any load, has worked faultlessly for 10 years or more. I am thinking of one further modification and that is to tidy up the inline fuses and mount a small fuse board somewhere under the bonnet to make a neater job of it all.

A very similar story here. However, if there's a solution to remove some control boxes and save some parasitic power draw then I'm interested. It would need to be a wire by wire description of what to cut/join etc though.

[Englishman]

Flatplane8 said:

I don't know if this helps, but I did this in a different way. I took the TVR headlight and fan plugs at the front of the car and used them to switch relays (with the relays switching heavier cable direct from the battery to the lights and fans). Thus the TVR wiring is only switching the relays on/off, with the power coming via a feed with less voltage drop. Also did this on the 3000M I had before and it helps to improve the brightness of the lights.

Not on a Cerb, but I used this technique to stop wedge instrument needles, especially the voltmeter, waving in unison whenever the indicators were on.

[Flatplane8]

Penelope Stopit said:

Your method will help many

The above diagram is more for those that have faulty control units or wish to bin the lot and start again

Purely out of interest, did you have a problem with the dim dip circuit holding the dip beam relay in?

Hi,

Yes I did, it caused buzzing of the relays. I cut the wire in the boot control box for the 'dim dip' function and it was all fine.

[Penelope Stopit]

Ok then, thank you for the reply

[Penelope Stopit]

Cleaned up

Updated

All information is now in the opening post

Enjoy

[Juddder]

So just to get my head around this mod - connecting Lights ECU A6 to Dim Dip Control Unit ECU A1 just means that the headlights get a full 12V feed when the side lights are on, rather than a dimmed feed as it would with the Dim Dip units still connected?

I can't remember off the top of my head but would this then make the 3 light modes on the Cerbera

- Off
- Side + Headlights (12V)
- Side + Headlights (12V)

or does the main beam disable the side lights (not with my car to check)?