Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Wiper elay

I have a 2020 GDi Plus 4 and have discovered the wiper delay isn't working. A garage has had a look and tell me I need to replace the wiper stalk as it's faulty. I believe it's the Lucas STC4016.

Before I do that can anyone tell me exactly how the circuit works? I can see there is a wiper relay fitted - is the timing for the delay controlled by the wiper stalk, the relay or something else in the ECU?

I'm thinking the wiper stalk is just a simple on/off switch that activates the delay elsewhere in the circuit?

If it is like the 3 7l roadster I would first swap one of the relays as they are identical to see if that works. The stalk is of Land Rover.

Les, the unique wiper delay relay has a built in IC offering two triggers. One appears to provide the three wipe on cycle when screen wash commanded. The other is activated by the wiper delay selection providing a varying off period. Other functions don't employ the relay.

Thankfully the whole wiper system is independent of ECU/BCU. Below is simplified diagram of similar system noting that relay has differing pin labels to the Wehrle one Morgan use.



If none of the delay selections work then break/make the two connectors at rear of wiper stalk. The smaller with just two wires provides the varying wiper delay selection to relay. Check relay connections similarly. If no improvement then replace wiper relay - Wehrle 60-201-002.

If needed I can confirm the wiper stalk is a Lucas STC4016 which could also be the culprit.

Please PM with email if you require a more detailed description of wiper workings for later Classics.

I had the same problem after the Clubsport tune was done and after pulling the relay out and back in again it all worked but did pack up again a few months later, on inspection I found one of the cables in the relay holder was not clipped in properly so was making contact with the relay. After getting the wire to connect properly I have never had the problem again.

Thanks for all the replies so far, I'm going to have a closer look at the car tomorrow. I'll report back.

All done!

Seems I had a similar problem to Tresco, the orange/green wire underneath the relay holder had become disconnected from pin 1. There isn't a clip in the holder so the wire has to be held in place underneath with a finger when pushing the relay into the holder. A gentle pull on the wire afterwards just to check it is connected to the pin on the relay. Strange that pin 1 doesn't have a wire holder, just the hole. It's the same on another holder I have for the spare wiper relay I carry next to the working one.

More worrying is that my local Morgan dealer said they had checked the wiring and that it was a faulty wiper stalk. They could order one up for me but the car would have to go back in to have it fitted!

Thankyou all for the guidance - as usual the forum members come to the rescue.

Great result Les That orange/green wire is one of the two I mentioned above in the smaller of two wiper stalk connectors. I believe it allows via a resistive array within the stalk, actuated by the four position wiper delay twist switch, a varying voltage to be applied to the delay trigger on the wiper relay, pin "I" - intervall in German.

The 6 pin wiper delay relay has a narrower "I" or 1 pin which probably explains why it's corresponding connection in the relay base is not fully captive and the norm for other relays is 5 pin. See here.

Thanks for bringing this to our attention and others beware when removing this relay for inspection/replacement!

Glad you solved it

Glad you fixed it Les, I actually drilled a bigger hole in the base so I could pull the connector through the base and push it directly on to the relay.

That's a good idea, I'll do that too.