Overdrive on the 740 TD 1986... Problèm

Hello,
I changed the overdrive on my volvo 740 td 2 years ago.
So, now I have an electric problem by pressing on the button of the control
lever maybe a problem of bad contact on the relai...

Has anybody an idea?
the garage owners live in France are not véry good on this type of car !

Thanks.
I am a French and sorry for my english writing

 

Is the transmission an automatic shift or or manual shift?

Duane

 

Bad solder connections in the overdrive relay are common. The relay can be
resoldered or replaced. Sometimes there are wiring problems (broken or short
circuiting) but the relay is easy to try.

Mike

 

The transmission is an manual shift.

Thanks

 

Another problem in relays is that since Volvos last so long, carbon can
build up on the electrical contacts, making them work intermittently or
not at all.

Very easy to remove: take the relay out of its case, soak a corner of
white paper in electric contact cleaner, and rub this liquid soaked
paper through the contacts several times.

Look for smears of black carbon: if you see any, the cleaning was a
success.

 

Thanks Mike,

Tomorrow, I changed the overdrive relay, because I thinks it is this because
when I fiddle with (touch) it, the red ligth on the board table can switch
off/on/off/on/off.......
Also, I remake the solder in relay but without succes...

Thanks a lot, Mike

Sherlock,

 

Thanks a lot...

I try that.

 

A test:

Ignition ON, Engine OFF, in 4th gear, Push Button. Dash light should go on.

If dash light stays off with the first button push, pull shifter further to
right and back, try push button again. If dash light goes on, change 4th
gear switch on transmission.

If dash light goes on with first push, leave on, get under car and check
wires at solenoid on left side of overdrive. Removing wires off solenoid
should make solenoid click with remove and put back on.

Also, be sure transmission fluid is at bottom of fill plug on left side of
transmission. Low fluid will not allow overdrive to engage.

If there is power at solenoid because solenoid clicks when dash light goes
on, there is a fluid problem inside the overdrive that needs to be fixed if
the transmission fluid is full.

Duane

 

Thanks Duane...