Engine cutting out due to faulty relay 109.

This relay was a black plastic-cased one. Silver ones are apparently more reliable.

I opened the relay by prising off the cover. Continuity checks found a dry soldered joint on the printed circuit board. Re-soldering the joint cured the problem, cost - zero .

ROYD

That's a good tip, but does rely on knowing a bit of electronics . I don't suppose you've taken any pictures of the offending item?

That's a good tip, but does rely on knowing a bit of electronics . I don't suppose you've taken any pictures of the offending item?

Aye.....would be good for a "How To...." section.

On the case boss if ROYD can provide some photo's I will add it.

relay 109.

Where does one find this relay? Engine compartment? ... more clues?

(Yes, I know I don't have a diesel)

Aye.....would be good for a "How To...." section.

Is there any interest in a few before and after pics of when I re-soldered a joint on my Relay 109?

Is there any interest in a few before and after pics of when I re-soldered a joint on my Relay 109?

Yes it would be of interest to do this:thumbup:

Hell for the price of the relay i'd buy the new modified one and know that it wont be giving up again.

The relay is located in the relay plate behing the panel in the drivers footwell (under the headlight switch).

The relays can be found behind the drop down panel just above the pedals, locate and remove Relay 109 by gently but firmly pulling it (mine was quite hot when I removed it, so take care):

Open the relay by carefully prising the outer case away from the base of the relay.

And pull the relay module out of the case:

Find the dry joint, on mine it was the joint shown in below image that is on the left hand side of the pad that is just above the letters Ab printed on the circuit board:

Re-solder joint, re-assemble relay, re-fit to car and fire up the engine!

Edited 25 February, 200917 yr by deedaw

To relive this thread, got the same symptoms on my 2000 Oct 1.9 TDI the other day, parked normally, after a few hours it just cranked indefinitely. Bought the 109 relay for ~4€, mounted it in a few minutes and voila it fired right up.

 

Although at this mileage and age ~340kkm I see it's not the first time it happened, it was changed some time before.