960 Gearbox (auto) error condition

[PRX]

Have seen a number of 960 auto gearbox blogs, here is some sound info and advice that came to me from 2 ex Volvo mechanics who run their own garage today near Oxford. My M reg 960 started with the flashing arrow and W-S-E button flashing. This started when on winter on very cold mornings.

They said that this was down to an over sensitive gear box oil sensor. Not worth changing due to cost, but to follow a routine that would reset the 'system' after a couple of minutes once the gearbox oil had warmed (shared with the engine oil) and sensor would be happy.

1. Run engine for 2 minutes.
2. Switch off engine.
3. Move gear selector to Neutral
4. Turn on ignition but do not start engine, wiat 4 seconds.
5. Turn ignition off. Move gear selector to to Park
6. Turn ignition on but do not start engine. Wait 4 seconds.

Amber warning / flashing lights should now extinguish.

Of course if your gear selector switch or gearbox temp sensor is faulty or the connections are correded, then it will not clear.

The owners hand book describes this condition as a safety mode, drive up to 40 miles to a dealership for attention. It does just start the car in winter mode - i.e. 4th gear. Not too much effort for the beef and torque of the 3.0 litre engine.

Be interesting to know if there is a way to by pass the gear box oil temp sensor, as it uses the engine oil, you know the oil level and temp from the engine management. Save resetting the sensor everytime it decides it had a cold night

[TheJoyOfSix]

Originally Posted by PRX

gearbox oil had warmed (shared with the engine oil)

The reset may well be true, but there is no way both gearbox and engine oil are shared. For a start there is no common point in either oil's passageways, and engine oil is totally different to ATF (Automatic Transmission Fluid).

[niloc]

As V6MAN says, there is no common connection between the engine and box. The auto box cooler lines run from the box, past the exhaust manifold then enter the engine coolant radiator. Engine oil stays with the engine, unless an auxiliary oil cooler is fitted (extra little radiator bolted near the main rads)

[GavinC]

As reco'd - I think - by others on this forum on the rare occasions my auto-box arrow behaves like this I park up, switch the engine off', handbrake on and then drag the selector lever from 'P' position to 'L' and back about 20 times. I understand that this cleans some 'contacts.' On restarting and setting off the flashing arrow's gone. And I have found that this works even if - on even rarer occasions - the car has slipped into 'W' driving mode with the lights flashing. But it slips into 'W' like this only when it is parked - never 'in progress.' On other occasions - if the car has not gone into full 'W' mode but the selector lights and arrow are simply flashing - I have simply ignored it and after a while it goes away. Sometimes takes a 100 miles to go away, mind you - and not necessarily on the same day's motoring, either. It appears to be much more likely to play up in damp, cool weather - particularly if the car has been left standing for a couple of days or more .

[Zaabje01]

Originally Posted by GavinC

As reco'd - I think - by others on this forum on the rare occasions my auto-box arrow behaves like this I park up, switch the engine off', handbrake on and then drag the selector lever from 'P' position to 'L' and back about 20 times. I understand that this cleans some 'contacts.' On restarting and setting off the flashing arrow's gone. And I have found that this works even if - on even rarer occasions - the car has slipped into 'W' driving mode with the lights flashing. But it slips into 'W' like this only when it is parked - never 'in progress.' On other occasions - if the car has not gone into full 'W' mode but the selector lights and arrow are simply flashing - I have simply ignored it and after a while it goes away. Sometimes takes a 100 miles to go away, mind you - and not necessarily on the same day's motoring, either. It appears to be much more likely to play up in damp, cool weather - particularly if the car has been left standing for a couple of days or more .

My 960 gave me a proper fright yesterday with the flashing arrow and W-S-E buttons flashing. Spent a few hours research and with crossed fingers, toe and eyes took the advice to "park up, switch the engine off', handbrake on and then drag the selector lever from 'P' position to 'L' and back about 20 times". It worked!!!

[Forrest]

Whether that “fix” will work or not depends on what error your gearbox has recorded. There is a common problem with dried grease on the PNP switch which it often will help with. Better to read the codes to know what you’re dealing with. There may be other problems developing as well.

See, for example, this thread where the fix helped but a loose connector might have been becoming a problem as well

https://www.volvoforums.org.uk/showthread.php?t=336049