Indicator problem after heavy rain.

So, last weekend my TF was sitting in the work car park for 4 days, 2 of which contained torrential rainfall.
Upon starting and driving home, the indicators didn’t work: absolutely no response to the stalk switch in either direction, nor the hazard switch. Roughly 25 miles home, in the early hours of the morning, with little traffic around, I tried the switches repeatedly, and after about 15 mins the hazard switch illuminated the little red warning light, but nothing else. Just before I got home, indicators and hazards started working as normal.
I’m thinking something got wet, and dried out on the way home, but what was it!?? It’s all fine now, but I’d like to do some preventative maintenance to stop it happening again.

I’d be checking the whole indicator circuit, checking and cleaning all the terminals, looking for signs of corrosion, also replace any blade fuses, these can get corrosion on the blades especially it they are of the alloy kind

Check to see if rainwater has been getting in and dripping onto the fusebox and the rear of the switches.

Take time to download the manuals and wiring diagrams from the Community, Downloads section of this site and also refer to the How Tos. If it is water ingress then you need to know how to stop this. You will also discover the location of the hazard and indicator flasher relays so that you can get them out and make sure they do not have residual water inside them.

The rain may be a red herring. There’s very little of that circuit where water can get in & cause a problem. If your indicators & hazard lights have taken leave of absence simultaneously look for a common denominator. The indicator relay is electronic & has been problematic with poor joints causing failures.
Whilst coasting towards an MOT my system failed & could find nothing locally as a replacement; the nearest was in Manchester.
With the MOT sorted I looked at the old relay & found two dry joints, having resoldered them I now have a spare.
The part number is YWT10003 & lives in the fuse board under the steering wheel. At least it does on my f.
M

Thanks for the answers so far.
I’m struggling to find the flasher unit, can anyone give me a pointer?

On the fuse panel under the dashboard

I’m afraid that the dog’s breakfast that is theTF workshop manual isn’t much help other than to say it’s the hazard flasher that also operates the indicators, it’s somewhere in the vicinity of the interior fuse box, in fact what it has told me is that there are 10 relays on the fuse board… of interest are relay #5 operates the L/H indicators and relay #7 operates the R/H indicators.
Check the hazard switch it could be your problem.
Check under bonnet fuse #4.
Check fusible links #6 & #5
Check interior fuse #23





















That’s all there is on the subject, sorry I can’t be of more help.
As I’ve mentioned elsewhere the manual was written not by someone with mechanical aptitude…. No it was written by someone with mechanical ineptitude!
Still now that phone books are a thing of the past, the police could use the manual as a substitute for interrogation purposes ( belting the living shit outta suspects with the phone book leaves no bruises and doesn’t hurt your hands.)

I haven’t had time to look at the diagrams yet but what I think we have here is a Lucas reply to a Pektron problem. I like to do a quick check on problems before I contribute & I Googled MGTF indicator relay & up popped my number one suspect. Having experienced a problem not too dissimilar to yours I made the incorrect assumption that your relay was faulty. And now it transpires that you don’t seem to have one!
I’m guessing now & I’ll see if I can verify this theory but there appear to be two standard relays doing the job & my guess is that the Pektron unit is controlling them.
I’ll check tomorrow & post back, unless I’m pipped by the Knowledgeable.
M

Well I couldn't settle without confirming my suspicions, so I come down stairs, brewed up & now having looked at the diagram can confirm that all the indicator & hazard warning lights are controlled from the Body Control Unit. There could be any number of reasons for adopting this system but money will be casting a shadow over it. Lets be honest the Lucas system was showing its age when the Mk2 tf came along & MG Rover were investing what they had to bring their cars forward. The development of a MEMS3 system with Pektron was a way forward & if the relays in the Pektron units had been more robust we might be talking about those units with the same "affection" as we do the Lucas system.
Sorry if you were mislead but I would be contacting Paul at Technozen & see what comments he has to make.
M

The indicator system does use the hazard system, so do the hazards work?
If not, I would suspect the hazard switch and flasher unit.
If yes look at the indicator switch, although its theoretically possible, I doubt both of those relays shit themselves at the same time.
As I mentioned check the fuses and fusible links mentioned not just having a squiz to see if they’re blown but check that there is no corrosion on the lugs or the connections.
Check all the wiring connections and the earthing points.

They seem to have taken a simple system that has stood the test of time, and made it unnecessarily complicated for no good reason, other than they could.
You had an indicator switch, a flasher unit, a fuse, some wires and some lights…… to add hazards to the system you had a hazard switch another flasher unit, wires, a fuse and some diodes to keep the left and right indicators separated when the hazards are not in use………hardly rocket surgery or is that brain science?

You can take a look at this thread https://www.the-t-bar.com/forum/roverlike-s-guides/97846-mg-f-tf-fuse-relay-listing where you can find position of indicator flasher for Lucas system or indicator relays (2 of them) for Pektron system.

As Airportable said if you have Pektron system (oval fob with logo in the middle) BCU unit operates thes two indicator relays and your best call would be to Paul @ https://www.technozen-electronics.co.uk/ since this well might be Pektron BCU problem.