[Baz C]

Please help? I have a 2016 Kadjar 1.5 d auto i get a message on dash check anti polution system. I ran car at 60mph in 4th but it didn't help. Then car started dropping into 2nd gear when going at 30mph. Message came up check auto gear box & check stop start. A friend put it on a code reader & it came up with code df394 but said changing gear shift drum malfunction 1 gear shift too long. RAC put a code reader on it & said it was either a bad earth or a bsi unit. Car had new gearbox 8 months ago.
Renault want £150 plus vat just to do a diagnostic check.

 

[ajc1200]

When my 2017 Clio was throwing up random messages and wouldn't start it was the battery - AA checked it, charged it, but had to replace it. They said it was a common problem following lack of use during Covid restrictions. Been fine since.

Worth checking?

 

[Baz C]

When my 2017 Clio was throwing up random messages and wouldn't start it was the battery - AA checked it, charged it, but had to replace it. They said it was a common problem following lack of use during Covid restrictions. Been fine since.

Worth checking?

Had the battery checked at Halfords & they said it was fine.

 

[Baz C]

Thanks but had the battery checked at Halfords & they said it was fine.

 

[Andrew Capp]

Has the battery had a digital load test and cranking test. May appear to be OK but the voltage could be getting pulled down during cranking.

 

[Baz C]

Not sure to be honest, Halfords checked voltage & amps & said it was fine. Tried to pull away in the car today & there was no power at all no revs nothing. Swithed it off & back on & it was fine. But still jumping all over the place when pulling away.

 

[Andrew Capp]

Did they give you a copy of the reading. You should have measurements for cold cranking amps, battery charge status, voltage and internal battery resistance. Cranking test should give you cranking time in milliseconds and the voltage during cranking.
May not be battery related issue but the figures would help to rule it out.

 

[Baz C]

Ah many thanks, no they just tested it & said it was fine. Could be my next step. Thanks!

 

[Baz C]

Just had RAC report back & it says that there was no comms on engine or gearbox control & suspects it is a bsi unit. Any thoughts?

 

[ours2012]

you mean they cannot diagnose it?

 

[Baz C]

The RAC said he suspects it to be bsi unit and said it will be a main dealer repair. The car had a new gearbox under warranty 8 months ago by Palmers but they have said that if it is the gearbox then they won't repair it as the warranty has run out. Surely that gearbox comes with a 12 months warranty? Just trying to establish if it is transmission fault or electrical.

 

[ours2012]

Could he actually get to diagnose the system?
or not
(No comms = no diagnosis)
so has he suggested/guessed its a UCH issue

 

[Baz C]

He ran a diognostic check & said he thinks it was either bad earth or bsi unit but unlikely to be bad earth.

 

[ours2012]

well I would go on a bad earth
And this Earth is either lose, or corroded

locate gearbox, and look for the earth, see if its still tight

 

[Baz C]

So the latest is it appears there is a fault in the wiring loom between the ecu & starter motor/gearbox. Struggling to get part because nobody from any of 3 local Renault dealers even bother to answer the phone or return calls when i leave message.
Mechanic is also waiting for Renault parts to email him back for 2 days now.

 

[Baz C]

So after not hearing back from the mechanic I have had a diognostic check done by Renault & it has come back a faulty gearbox inbox speed sensor. Will update again once this has been fitted.

 

[twodogs]

If you are still on your first battery I would be suspecting this. Also why was the original gearbox changed. Is this the EDC (DC4) auto box? Is Palmers a Renault garage? If yes to the last two did they do a full software calibration/update after they replaced the gearbox. Bad connections, low voltages and buggy software are the prime candidates.

 

[Baz C]

Palmers are not a Renault garage. I had a clonking noise when braking at slow speed to be not the brakes but gearbox & fitted a new one under warranty but this did not stop the clonkkng noise. I will go back to them & find out exactly what they fitted & get another battery test done. Would a faulty battery keep putting ths gearbox into safe mode?

 

[twodogs]

Would a faulty battery keep putting the gearbox into safe mode?

The gearbox is controlled and managed by an ECU. The ECU has a control panel (PCB) like any computer that reads inputs from sensors (like your speed sensor). These inputs are mostly small variations in voltages. If these are inaccurate or cannot be interpreted the system will record a fault. Gone are the days when a car would run happily on 10, or 14 volts (or even without a battery at all). If your battery is the original one it is now six years old.

 

[Baz C]

The gearbox is controlled and managed by an ECU. The ECU has a control panel (PCB) like any computer that reads inputs from sensors (like your speed sensor). These inputs are mostly small variations in voltages. If these are inaccurate or cannot be interpreted the system will record a fault. Gone are the days when a car would run happily on 10, or 14 volts (or even without a battery at all). If your battery is the original one it is now six years old.

The gearbox is controlled and managed by an ECU. The ECU has a control panel (PCB) like any computer that reads inputs from sensors (like your speed sensor). These inputs are mostly small variations in voltages. If these are inaccurate or cannot be interpreted the system will record a fault. Gone are the days when a car would run happily on 10, or 14 volts (or even without a battery at all). If your battery is the original one it is now six years old.