Rail commuters have faced delays this morning (Friday August 25) between Horsham and Dorking.
A fault with the signalling system between the two stations meant that trains had to run at reduced speed on some lines.
This caused delays of up to 15 minutes.
Trains were still able to run on this line, but had to stop before a particular signal and call the signaller in order to confirm that it was safe to proceed.
The service has now returned to normal.