water-red light flashing Sometimes

[chickenkoop]

the water red lght sometimes stays on after start up, turn off then start up again it goes out, i have read the wiki about the red light faults/ what it could be,
the water gauges does rise up after she's been running. is it anything to worry about as i'v got to go Cov to bolton on sat,
any help with this issue,

[toomanytoys]

Is there water in the pressure tank?? should be full...
does the gauge sit somewhere in the middle or just below? ("rising up" means nowt if you dont tell us from where..)

[CovKid]

Yes to both of those (I know the bus he's referring to). Apparently it doesn't overheat and the red light is very intermittent.

[clartsonly]

mine is a bad earth, if I switch the engine off then on again it stays off for the rest of the journey.

[Ian Hulley]

Bad earth, faulty wiring, dodgy sensor (known fault with GSF replacement part)

Ian.

[chickenkoop]

ok will check the lot, thanks,

[joe75]

mine does the same. i think its the GSF sender I put in. will get a proper VW one and hope for the best!

[OriginalSeries2]

Happens to me every time I switch my headlights on - first time it happend I roasted cos I put the heater on full.
Now I just switch lights off to check that the flashing red light stops!
I suppose its a fault in the connector block behind the dash?

[Mocki]

Happens to me every time I switch my headlights on - first time it happend I roasted cos I put the heater on full.
Now I just switch lights off to check that the flashing red light stops!
I suppose its a fault in the connector block behind the dash?

no its a bad earth, does it do it when you brake and have sidelights on too?
if not, the earth is at the front, if yes, its at the back...

[AngeloEvs]

post '86 van, whip the coolant level module 43 out of the fuse box, if this cures the problem then the fault is in the coolant level circuit, usually a duff earth or connection at the earth crown next to the fuse box, connection at the level sender, etc. If it carries on then the fault is probably in the multi connector at rear of dash, loose nut behind temp gauge causing the gauge to self test intermittlently, poor battery earth will also cause temp led to stay on but not bad enough to affect starting. Intermittent fault with module as a last resort.

[OriginalSeries2]

Thanks Mocki & AngeloEvs
I'll have at look at these bits at weekend

[CovKid]

You didn't believe me when I said it was giving a faulty reading did you Rob?

Van passed by the way with Marcus in attendance.

[Pootle]

post '86 van, whip the coolant level module 43 out of the fuse box, if this cures the problem then the fault is in the coolant level circuit, usually a duff earth or connection at the earth crown next to the fuse box, connection at the level sender, etc. If it carries on then the fault is probably in the multi connector at rear of dash, loose nut behind temp gauge causing the gauge to self test intermittlently, poor battery earth will also cause temp led to stay on but not bad enough to affect starting. Intermittent fault with module as a last resort.

I'm having the same intermittent problem.

With the engine NOT running, if the LED is NOT flashing I can make it start by turning on the headlights, indicators and brakelights together. If I then remove module 42 (my 1989 wbx doesn't have a module 43) the LED stops flashing a few seconds later (not immediately).

The level sender is about 6 months old but this problem is recent. I bought it from Euro Car Parts. The connections at the sender are clean.

AngeloEvs, is this the behaviour you are describing above?

Also, is there a known problem with some aftermarket senders?

[CovKid]

Yep, check for poor earth as a starter

[AngeloEvs]

I don't understand why there should be problems with any after market sender since it is just two metal probes in a plastic moulding. Theoretically the only faults that could develop are that the sender probes break internally at the connection to the terminals, they get coated with crap or the probes are the wrong length or distance apart. People have reported problems with aftermarket ones so I'm not going to dispute that fact but it is odd given the simplicity of the sender.

The sender connections should be checked and one should have a good connection to earth. This earth connection is a problem given that it has to meander through two connections ( in the black connector box LH side of engine bay) before it finally arrives at the earth point under the ignition coil.

The second Earth problem is the one that earths the module 43 (or 42) and this is located on ther crown earth next to the fuse box.

The third problem is the temp gauge nuts are loose, particularly the centre one but the LED would still behave erratically even with the module 43 removed.

The fourth earth problem is the starter battery itself which can cause erratic behaviour of the coolant led even though the the van starts fine.

Removimg the unit 43 isolates the fault to the coolant level part of the system. Even though removed, the coolant LED will still self test as normal and it will still operate if coolant temp rises significantly