GEARBOX FAULT SERVICE REQUIRED
Discussion
good morning everybody
Just got "GEARBOX FAULT SERVICE REQUIRED" , drives normally , all gears present and correct , paddles work, sport mode works, retrieved 2 codes, P0705 "gear position signal error" , P0471 "torque converter clutch permanently open".
battery new and fully charged, Has any body had this issue?, any help greatly appreciated,
craig
Just got "GEARBOX FAULT SERVICE REQUIRED" , drives normally , all gears present and correct , paddles work, sport mode works, retrieved 2 codes, P0705 "gear position signal error" , P0471 "torque converter clutch permanently open".
battery new and fully charged, Has any body had this issue?, any help greatly appreciated,
craig
Well, the codes at least explain why it still drives the same from an operator's standpoint. With an open clutch, it'll lose some efficiency and increase your fuel usage but should otherwise be fine as you've noted. Don't know how difficult it is to replace the GPS, but that should fix the problem and allow the clutch to close when in the appropriate gears.
Its Fixed!!, the fault code definition in the workshop manual for P0741 "Torque Converter Clutch Permanentley Open" gives 6 steps in Fault Analysis,
1. check transmission fluid, surprisingly mine was 800ml low (more on that later), so topped up.
2.next check voltage at trans connector , mine was 11.8V (should be 12V)
3 check condition of connector ( I know from experience that the seal on this connector can fail and fill the plug with oil) mine was ok
So now trans topped up (ZF Lifeguard from Euro car parts), so voltage , my Varta battery was 2 years old but i decided to replace it anyway ( these things seem to eat batteries!!)
my device still wouldnt clear the code, so went out for a test drive on various roads , drove steady as one issue caused by non lock up is overheat and i didnt want that! , i could see torque converter lock up occuring in 4th & 5th on the rev counter, then half hour in the warning message and triangle went off and the digital speedo returned.
carried on for another hour with a bit more vigour , all good.
Observations
Low trans fluid, on cold start there was always an intermittent whine like aerated fluid in a power steering system but from the back , usually 30 seconds and it was gone. i now know this was an indication of low fluid level.
the procedure for checking the fluid states the trans be between 50 and 80 degrees when you take the plug out , now for the controversial bit, a mate runs a big automatic transmission repair business , at the start of this job i talked to him to get a bit of advice, he said " do it cold " to my mind that would overfill it but this lads worked on more ZF6HP 26 than anyone i know.
any way i did it cold so we`ll see.
Battery, mine was 2 years old , whenever i did the engine oil priming it would spin it over lovely so i didnt suspect it but these cars are incredibly fussy about battery voltage, one odd thing when i drove to work to get it on the ramp ( only about 2 miles at 30 mph ) i parked up for a few hours and when i came to restart it accused me of a "high temp engine stop" .
hope this helps somebody with similar problem
thanks to dbvolante driver for your help
craig
1. check transmission fluid, surprisingly mine was 800ml low (more on that later), so topped up.
2.next check voltage at trans connector , mine was 11.8V (should be 12V)
3 check condition of connector ( I know from experience that the seal on this connector can fail and fill the plug with oil) mine was ok
So now trans topped up (ZF Lifeguard from Euro car parts), so voltage , my Varta battery was 2 years old but i decided to replace it anyway ( these things seem to eat batteries!!)
my device still wouldnt clear the code, so went out for a test drive on various roads , drove steady as one issue caused by non lock up is overheat and i didnt want that! , i could see torque converter lock up occuring in 4th & 5th on the rev counter, then half hour in the warning message and triangle went off and the digital speedo returned.
carried on for another hour with a bit more vigour , all good.
Observations
Low trans fluid, on cold start there was always an intermittent whine like aerated fluid in a power steering system but from the back , usually 30 seconds and it was gone. i now know this was an indication of low fluid level.
the procedure for checking the fluid states the trans be between 50 and 80 degrees when you take the plug out , now for the controversial bit, a mate runs a big automatic transmission repair business , at the start of this job i talked to him to get a bit of advice, he said " do it cold " to my mind that would overfill it but this lads worked on more ZF6HP 26 than anyone i know.
any way i did it cold so we`ll see.
Battery, mine was 2 years old , whenever i did the engine oil priming it would spin it over lovely so i didnt suspect it but these cars are incredibly fussy about battery voltage, one odd thing when i drove to work to get it on the ramp ( only about 2 miles at 30 mph ) i parked up for a few hours and when i came to restart it accused me of a "high temp engine stop" .
hope this helps somebody with similar problem
thanks to dbvolante driver for your help
craig
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