Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Do you hate electrics ?

Over the last few years my 2011 4/4 has had an intermittent fault on the washer circuit.
Basically I manage to fix it, & it lasts for months. The fault is a dead short to earth on the feed wires to the washer motor. ( not the motor) therefore operating the washers blows the no8 fuse. But the wipers work. I have no idea what I do to fix it as each time it is a different “jiggle”
I am quite knowledgeable on electrics, hence today decided to pull as much as possible apart and check as much as possible. Realised that I wasn’t getting anywhere so put it all back together. Now the washers work but the wipers don’t but the fuse doesn’t blow so the wiper feed is now open circuit.
Does anyone know why the live feed to the washer motor has two LGB light green black to the plug as the available wiring diagram only shows one. Also I am fully aware that the loom is for both left & right hand drive. Things tend to be duplicated but both washer motor plugs have the duel feed.
Any ideas appreciated.
Thanks.

Your description of a dual feed seems like it is just a link from one circuit component to another, a bit like a daisy chain. That possibly being the case then perhaps there may be corrosion or other reasons for poor contact between the two wires at the point where they are joined together..?

Good luck.

From fuse 8 there is a single green cable providing power to 5 way wash/wipe control plug. The power, also on green cable then loops back from same pin on this plug to the 5 way wiper motor plug. It's likely there is currently a fault on this plug or matching socket causing loss of power to wiper motor.

The wash/wipe plug also has two light green/black cables on same pin feeding switched power to each of two washer positions to cover LHD and RHD versions (similar for brake fluid sensor). Might be worth checking that the unused washer connector at other side of engine bay is not causing any mischief.

A check for cable chaffing on above mentioned cable runs may be an idea if previous suggestions don't provide solutions.

Thanks for the info. Apart from a multi meter, I also have a circuit tester. Basically it creates a tone that you can chase along the loom using a wand. In theory if their is an open circuit or short the wand will “sense” the fault. So far from pump plug to column, via relay seems good.
Both plugs for the washers left & right have the twin LGB leads. So far I have not actually taken off the column stalk as it didn’t want to come out, but think that was more me being too careful. Does anyone know if the black insulated lead that is part (tail) of the switch is actually the wash wipe circuit?
No sign of damage but it is tightly wound around the column switch & could be the area causing the problem. Can’t get the tester on it at that point.
Thanks.

Try the plug just behind the washer bottle by the firewall, it's a common reason why the wipers stop.

If both screen washer pump plugs have two LGB leads each it's likely they loop through to each other as well as having a feed each from washer switch, although wiring schematic does not show such. On later models one of these cables triggered a dedicated wiper delay relay such that wash would allow wipers to operate a few strokes. Guess you don't have this option but may explain.

The wash mode on column wiper switch puts intermittent power onto LGB cables. No info on switch so cannot comment on tail colours but unlikely to be black as it's a live switched feed. A fault on the switch could certainly blow fuse 8 though and cause wiper failure although there is no intended ground connection on this plug and therefore the switch it connects to. Just occurred to me that another possibility for blown fuse is a stalled washer pump motor, which could be intermittent of course if partially jammed.

If you still have the situation where washer works without blowing fuse but wipers don't, I would first check there is +12 volts on green cable pin at wiper motor plug (with ignition on). You could also check for good local ground connection at this plug on pin corresponding to black cable. Also confirm these main power feeds follow through socket to motor if possible. I think it's this plug/socket connection Keith was referring to. The other three cables each with LG tracer correspond to fast, slow and intermittent wipe as selected on column switch BTW.

If wiper motor feed seems ok then turn your attention to wash/wipe switch.

I too would suspect the wash/wipe switch because it is common to both faults.

David Byrne

Any progress here IcePack?

Well sort of. All working but I have no idea what I did to achieve it.
Basically put the column shroud back together ( I had not removed the stalk)
& unplugged & replugged the wiper plug. I had replaced the relay earlier. Anyway think the short May have been in the switch stalk area & lack of wipe just the wiper motor plug.
Much appreciate the pointers what to check. If it goes again I will go straight to the stalk.

Sometimes the mere act of unplugging something and plugging it back together can cause the male and femail parts of the connection to rub together and clean off some crud making for an improved connection. It is also possible that in some cases the plug and socket arrangement is not fully snapped together or that the pins may not have been ideally terminated or ideally seated in the multiplug... There are more than enough in the way of variables to provide confusion and frustration, but with a bit of determination you have got there... For now..