Car electrics. Anyone here any good?!

[Tom K]

Find it hard to believe any Honda of this age doesn’t have some sort of dimmer on the gauges, especially as there are lots of questions all over the internet for the same problem. The solution mostly are a replacement or by passing the dimmer unit. As an aside if it is just a basic circuit it would only need a live and an earth and both would be common to all of the bulbs the earth will be common to most of the cluster so there is either a break in the track for your live or it runs through a dimmer. Have you looked on the CRV forums for solutions?

 

[stuart little]

In the good old days cars were hard wired. Fault finding needed no more than a bulb or a simple meter to test continuity. With a little effort almost anyone, including me, could fix faults.

In the good old days few cars had aircon, electrical seats, sat-nav, electric windows, integrated media, electronic fuel injection, central locking, multi speed wipers and fans etc etc etc. Whether all these are strictly necessary to get a ton of metal and contents from A to B is debatable.

Partly due to all this complexity we now have cars which are much safer, more economical, less polluting, more comfortable and faster than their automotive ancestors from the 1960s and 70s.

Downside - when things go wrong they can be very difficult to remedy. But typically things go wrong infrequently - in the last 15 years I have had 3 cars (1 new, 2 s/h) and covered ~250k miles during which I have had one problem related to fuel injectors (cost ~£100 to fix).

My automotive ancestors may have needed 2 engines, 5 decokes, 3 new clutches, etc etc.

On balance I will happily live with the risk of a complex electrical failure than go back in time 4 decades. This is of course no comfort to the OP!

I remember seeing more than one Morris Minor with 'brake lights' on the front when the twin filament bulbs short out!

 

[Tom K]

I remember seeing more than one Morris Minor with 'brake lights' on the front when the twin filament bulbs short out!

Not just Moggy's its a common fault caused by putting a single filament side light bulb into stop/tail bulb holder.

 

[Tom K]

Try looking here? https://www.crvownersclub.com/threads/dash-lights-go-out-when-i-turn-headlight-on.135033/

And perhaps try this? pull cluster, unplug battery first, unplug blue and green connecters ,locate red wire on blue plug,( next to red/black wire) splice into -do not cut red wire, run a splice wire (keep it red so you know what it is) to a suitable ground, steering column bolt is a good ground , this is the negative illumination circuit . the multi shorts to ground when disrupted usually due to aftermarket accessories, so the lowdown is positive flows thru cluster and negative comes out of cluster ok ,but it will not flow thru the multiplex unit which controls brightness, once you "steal" the ground before the multiplex ,lights will activate thru headlamp stem switch ,because the bad multi controls brightness the lights will be non adjustable and will only light up all the way not hard to due requires only a phillips screwdriver, and the method you choose to run a new ground wire .thanks for reading, oh and good informative club glad I joined!! window guy 02 ex black central ct.

 

[Spectric]

Find it hard to believe any Honda of this age doesn’t have some sort of dimmer on the gauges,

Yes it is odd and all the wiring circuits I have for the Mk 2 show a dimmer but it does not look like a dimmer, it is a button that changes the display from total mileage to trip but you can also rotate left or right a few degrees which either steps the brightness up or down and you get a beep at min or max rather than the old style variable resistance which suggest it is controlled by the cluster micro.

 

[Cozzer]

Find it hard to believe any Honda of this age doesn’t have some sort of dimmer on the gauges, especially as there are lots of questions all over the internet for the same problem. The solution mostly are a replacement or by passing the dimmer unit. As an aside if it is just a basic circuit it would only need a live and an earth and both would be common to all of the bulbs the earth will be common to most of the cluster so there is either a break in the track for your live or it runs through a dimmer. Have you looked on the CRV forums for solutions?

As discussed very early in this post, there is no dimmer.
As you say, there are lots of similar problems - mainly dealing with tail lights and dash light failure - but none exactly the same, except for a Yank job who claims to solve the problem by replacing the dead bulb nearest the blue connector. Suffice to say, this was tried to no avail.
Have checked CRV forums.

 

[Cozzer]

Yes it is odd and all the wiring circuits I have for the Mk 2 show a dimmer but it does not look like a dimmer, it is a button that changes the display from total mileage to trip but you can also rotate left or right a few degrees which either steps the brightness up or down and you get a beep at min or max rather than the old style variable resistance which suggest it is controlled by the cluster micro.

Some models have 2 buttons, one to the left of the fuel gauge, one to the right of the temp gauge.
Mine has one, left of the fuel gauge.
Total mileage shown on first press (unless already showing, of course!)
Next press, Trip A distance.
Next press, Trip B distance.
Next press, Total Mileage again.
Twist left: it won't.
Twist right: it won't.
Press in and twist: it won't.

Even the manual states "Instrument Panel Brightness" (for some types)

 

[okeydokey]

I would see how much a used item on ebay costs, btw if its doesnt work send it back and get a refund.

 

[Tom K]

Well the fix I cut and pasted from the CRV forum was about a problem that relates to the same fault but also states changing the clock doesn’t help as the fault is in the multiplex unit whatever that is. Maybe I misread the Wiki page but it seemed to suggest that the vehicle has limited trim options so unless you have some sort of limited production model it would seem your switch could be damaged. You may be on the wrong track though if the light on buzzer failure coincided with the lamp failure it could be that at fault.

 

[Spectric]

but also states changing the clock doesn’t help as the fault is in the multiplex unit whatever that is.

If you look at this diagram I posted it shows this multiplex unit but as a CPU and is not applicable unless you have the dimming controller. I would assume that the box marked *2 is the alternative ground arrangement when the dimmer is not used, it bypasses the mosfet that is controlled by the CPU. This problem should not be causing the OP such a problem as without this dimmer it is just a case of a 12 volt supply and a ground, they have confirmed a supply to the cluster which means it is more than likely to be the grounding side which is via C on the diagram which is a black wire on pin B15.

 

[Tom K]

The answer on CRV forum says that red wire provides negative switching and the fix is splicing a wire into it and giving additional earth which will turn on gauge illumination but at the expense of adjustment? But you are the bright spark here what do you think?

 

[Spectric]

The tail light relay is low side switched by the combination switch on the colomb but it supplies a live feed to the cluster via a Red / Black wire which has been confirmed as live. The power to the side lights and such is Red / Yellow. So if live is getting to the cluster then all the OP needs to do is 1) confirm this live is getting from the cluster connector to one side of the bulbs and 2) that the other side is grounded.

The multiplex module performs these functions,

So the reason people seem to jump on blaming this module is because there are wires from the tail light relay to the multiplex module but as far as I can determine they are only to operate the lights on reminder function, why not just a simple buzzer I here you ask.

If you want to get really confused then look at how Honda have wired the headlamps!!! Most vehicles will use a relay to reduce the current through the switchgear, but not Honda. They use a relay to provide power to turn the headlamps on via a 15 amp fuse but then use low side switching to change between the full and pass beams at full current through the switch gear.

 

[Cozzer]

I would see how much a used item on ebay costs, btw if its doesnt work send it back and get a refund.

Mrs.Cozzer is voicing a similar suggestion.
An unusual event - me being able to spend money - but I suspect it's something to do with the fact that she doesn't drive and I do.
"Cozzer Taxi".
I think you get my drift....
She actually passed her test over 30 years ago (first time, after 20 lessons) but has literally never sat behind a wheel since.
Don't bother asking why.
I have, many times, and I'm yet to get any reply other than "I have my reasons".
Amusingly she updated her licence after an address change, because she uses it as ID when required.

That's one reason why all this is taking time - apart from my own ignorance in electrical matters, and the fact that it's the sole vehicle, whenever her ladyship wants driving somewhere, I have to put all panels etc. back!

 

[Tom K]

Yebbut, he says that the warning is not working

 

[Cozzer]

....so unless you have some sort of limited production model....

It's a "CR-V I-VTEC SE Sport" according to the V5.

Rare?
Wouldn't think so.
I'd also take the word "Sport" with a large pinch of salt!

 

[Tom K]

No I didn’t think it would be anything rare or unusual, let’s hope the new unit sorts it!

 

[Spectric]

Ideally you would be better of going to a salvage yard and actually trying the new unit there, saves so much time and fuss because you can all to easily fix one problem but end up with another.

 

[Tom K]

I would see how much a used item on ebay costs, btw if its doesnt work send it back and get a refund.

Please don’t do this nobody advertises goods for sale for them to be used as test beds for parts cannon mechanics. If you buy it it’s yours! Over a 45 year period while I worked in the motor trade I had thousands of parts delivered that had been tested and damaged or a used part put in the box, you have no idea how frustrating this is for an honest mechanic trying to get a vehicle back on the road for an honest decent customer on a tight deadline.

 

[Cozzer]

Ideally you would be better of going to a salvage yard and actually trying the new unit there, saves so much time and fuss because you can all to easily fix one problem but end up with another.

Wife, or instrument panel?!

 

[Spectric]

I can say that you may be pulling your hair out trying to fix this but it is equally as frustrating for me because it is something that is so easily fixed but I can only advise from a distance.