Volvo: Transmission failure, yellow arrow, transmission failure

Question
Hi,my father in law has a VOLVO 850 GTL 1984 and was driving the other day when a yellow arrow lit up on the dash,and soon after all transmission was lost, it would select reverse briefly but now there is nothing, I have had a brief look but there is nothing evident.Any input would be very much appreciated.
Regards Dave j

Answer
Dave,
If the arrow is lit there is a very good chance that there are some codes in the trans control unit. You can take it to someone that can read those codes and diagnosis it for you. See if the trans fluid is black and burnt. If it is the trans may need to be replaced. It is very common to have the trans in that type of car go out. A good used trans will be about $700.00 to $800.00. Labor about the same. Have a rear main engine seal installed at the same time.