Dashboard errors!

[mercrocker]

I apologise if this is a resurrection of previous thread content but seem unable to currently access the very useful Wiki sections...... 
 
Got a 1.9DG (no tacho).   All of a sudden I find the coolant light coming on when the headlights are switched back off after having been on.  In conjunction with this I've also lost my panel light and no amount of fiddling with the dimmer is bringing them back (dimmer always been a little temperamental).   There also seems to be some faint illumination of random other warning lights in the central cluster.   
I would add that my fan switch works normally and coolant level (in the engine bay tank) has not dropped in the slightest.
 
Is this indicative of a wider problem at the fusebox/relay end or is it likely a breakdown of connectivity somewhere in the instrument cluster?    
 
Any advice welcome before I go back up the storage unit and try and get to the bottom of it.....!  

[AngeloEvs]

Check the condition of the spade terminals at the earth crown next to the fuse box.  The headlights and the coolant warning LED Trigger module (Located in the fuse box marked 42 or 43) are both earthed at the earth crown and can break up or oxidise.    You could also remove the module 42 or 43 and check if that clears the fault as it is extremely sensitive to bad earth problems that will trigger the Coolant LED.

[mercrocker]

Very helpful....I'll check that first and report back.   Don't know if I will be up the barn very quickly but I'll definitely report back.  Hopefully it will be that simple and probably related to having been stood for a month or so..... 
Cheers!

[mercrocker]

Had a chance to check the van again this morning.   Coolant level brimful in the engine bay tank and clean and pink as it should be so that confirms my hope that the coolant light was an erroroneous one.  
 
Pulled relay 43 (42 not present on my van) and the dashlights and warning lights all behave normally (light switch on and off) so assuming this is the fault.  New one being sourced today.... 

Thanks again!

[Mocki]

Module 43 and 42 are the same , you have one or the other . One is updated version of the other , but i cant remember which is which ?

make sure you clean and ensure all the earth points are clean and good connection . Thirty plus year old connections tarnish and become bad connections 

[mercrocker]

I shall give the board a good clean before putting my nice new Brickwerks relay in....Thanks again for the info!

[AngeloEvs]

Module 42 and 43 rarely fail.   As already  advised, if the fault is still there then check the condition of the spade terminals at the earth crown which is located on the pillar next to the fuse box.    The headlights and Module 43 both earth at the crown where there are a number of cables sharing that earth point.   Module 43 will trigger the coolant LED if its' earth is poor.

[mercrocker]

OK.  Since posting I have replaced Relay 43 with a new one from Brickwerks.  The fault persists.   The fault also persists with the relay out altogether.   Initially when I pulled the (original) relay the fault seemed to clear in as much as I got dash illumination and a normal response from the coolant warning light/needle. 
 
Situation now is - 
 
No dash illumination.  Incorrect warning light behaviour (no blue mainbeam light and a flicker onto the red ignition light).  High reading on the temp gauge and flashing coolant light whenever the headlights are switched back off after having been on. 
 
I propose to clean the contacts (presume using a switch cleaner unless anyone has a better recommendation) at the earth crowns but I am also wondering if there is an issue in the instrument cluster with the infamous blue circuit or some kind of earth problem in the dash.....

[AngeloEvs]

Its a case of elimination.   The dash should be removed then inspected with a Bench Test of all functions to establish wether there are any problems with the Membrane Ribbon circuit.   If all OK you can then focus on other possible faults/causes.  I can carry out a full bench test but the dash would have to be sent to me.

 

[RogerT]

I had problems with 42, a helpful chap (marlinowner) offered to check my original and new replacement on his known working van - both were faulty. A shame I can’t offer the same for you as my van is well out of action. But someone else might…

[mercrocker]

I had problems with 42, a helpful chap (marlinowner) offered to check my original and new replacement on his known working van - both were faulty. A shame I can’t offer the same for you as my van is well out of action. But someone else might…

Thanks for the thought!   I would hope my £32 Brickwerks relay is better than the 35 year old one in the van though....!   I've confused myself by testing the van with the relay out but ignition OFF when of course the fault doesn't show - it is when I turn the ignition on and most of the warning light wiring becomes live that I get the fault.   Good shout, though, I may be able to swap with somebody I know just to eliminate it.

[mercrocker]

Its a case of elimination.   The dash should be removed then inspected with a Bench Test of all functions to establish wether there are any problems with the Membrane Ribbon circuit.   If all OK you can then focus on other possible faults/causes.  I can carry out a full bench test but the dash would have to be sent to me.

Methodical electrical tracery is a bit beyond me - I jump to conclusions and hunches far too easily!   You're right, though, it needs to tested properly.   When you say "dash" do you mean just the instrument cluster/pod...?

It might come to that if I cannot sort it locally.

[AngeloEvs]

Sent you a PM