Dim-dip fault

amarshall · Post by **amarshall** » Sat Sep 30, 2006 12:33

Strange one - the pods come up Ok with sidelights on and ignition switched on, but the headlamps don't illuminate.

Normal Dip & Main Beam is fine, all relays & fuses are OK - does anyone have any thoughts ?

I'd prefer to keep dim-dip working rather than bypass it.

dpr59 · Post by **dpr59** » Sat Sep 30, 2006 13:40

Somewhere in the circuit there must be a voltage regulator to apply the reduced current to the lights.

In the relay perhaps.

I pulled the fuse on mine when I got the car, so don't have dim dip now.

dpr59 · Post by **dpr59** » Sat Sep 30, 2006 17:17

How about dim dip control moduel (MH07 in the manual)

alanmoss · Post by **alanmoss** » Sat Sep 30, 2006 17:45

There are two relays for the dim-dip located in the passenger (left) footwell area. These are the top two to the front of this lot. The upper one (lebelled S in the owners book) is the dim-dip control relay, and the one below it (labelled T) is the dim-dip motor relay). It sounds like the control relay is on the blink but the motor one is okay. Since dim-dip was removed as e legal requirement some time ago I assume that if you didn't want it you could just remove both relays. The pods will then only come up when you go to headlights on position.

Alan

amarshall · Post by **amarshall** » Sat Sep 30, 2006 18:01

I've swapped all relays and fuses for known good ones - the relays feel like they're clicking on correctly.

alanmoss · Post by **alanmoss** » Sat Sep 30, 2006 19:56

Maybe it is the Dim-Dip module then. This is mounted at the top of the bits in the left footwell. Sorry, don't know anymore about it.
Alan

pedro · Post by **pedro** » Tue Oct 03, 2006 17:17

I had this fault once. there are some fuses in the left hand piller with the relays. my excel is a 90 model. Starting at the top there are two fuses then there are two relays togther below these are two fuse mounts and below those there is another relay and two more fuses. I changed these fuses in between the relays and the problem was sorted.
There are also two fuses in the bank of relays under the drivers steering wheel, the fuse numbered 25 rings a bell but may be getting confused with the retractor circuit.

amarshall · Post by **amarshall** » Tue Dec 05, 2006 20:43

For a while (88-89?) there was a legal requirement for a "dim-dip" capability on all cars sold in the UK. The idea was that if you tried to drive with just sidelights, the headlights would come on automatically, but with a dimmer beam than usual.

Hence you got :

sidelights for parking
sidelights + dim-dip if you forgot to put the headlights on yourself
sidelights + normal dip or main beam if you remembered.