DISCO4.COM - View topic - Dashboard Lights Up like a Christmas Tree in cold weather!

Calcul@tor

Member Since: 08 Mar 2006
Location: Middle England!
Posts: 810

2012 Discovery 4 3.0 SDV6 XS Auto Galway Green

Dashboard Lights Up like a Christmas Tree in cold weather!

Just before Christmas, virtually every orange warning light on the dashboard plus the red airbag warning light came on when I started the car one chilly morning. Various other warning messages also appeared including no HDC etc etc.

Once the car had warmed up and was restarted, all but the airbag light cleared.

LRA duly attended, plugged in and reset multiple "communication error" warnings.

Next morning, same problem, so off to the dealer.

They eventually diagnosed a loose battery connection and "issues" with the parking break that would be dealt with by the Vehicle Enhancement Program. Both were done and the Disco passed all tests.

Until this Saturday night that is, when it was a bit cold here again, and on came all the warning lights - again! Once the car warmed up, they cleared with a re-start and as it has been milder since, they haven't reappeared.

I'll take it back to the dealers, but until it goes cold again, it's going to be very hard for them to find / cure / prove.

Anyone got any suggestions or advice? Why is it only happening when it's cold (but probably not necessarily freezing - although I'm not sure exactly how cold it has to be!)?

Thanks D4 XS MY12 Galway

8th Jan 2007 10:27 am

Winger
Site Moderator

Member Since: 15 Feb 2005
Location: UK
Posts: 3428

2016 Discovery 4 3.0 TDV6 HSE Auto Aintree Green

It's an old problem, and seems to afflict manuals more than autos. It is down to the cold weather and a combination of gearbox oil viscosity and possibly higher battery usage during cranking. This was supposed to have been fixed by a TSB, and your dealer should be aware of the problem - it was much prevalent last winter.

There is a gizzmo in the gearbox/transfer box that does a start-up dance (it travels along its rail, and back). As the oil is a tad heavier than usual, the procedure can take longer than the software expects, resulting in error messages. These should just disappear once the engine has actually started and is running - if they don't then is sounds as though the fix has not been applied to your car. I see if I can dig out the TSB number that covers it (if I recall, it is a transfer box issue). The vehicle enhancement programme, may not have covered this one, even though it was supposed to ensure all modules were fully up to date.

The airbag warning light sounds like a different issue.

8th Jan 2007 2:01 pm

Calcul@tor

Member Since: 08 Mar 2006
Location: Middle England!
Posts: 810

Many thanks for the response!

The airbag light only came on before it went in to the dealer. It didn't come on again last time. So that might be something different.

If anyone knows the TSB number, I'd be very grateful.

Also, does anyone know whether this should have been part of the VEP? D4 XS MY12 Galway

8th Jan 2007 3:02 pm

DN
D3 Decade

Member Since: 23 Jun 2006
Location: W.London.
Posts: 2344

2006 Discovery 3 TDV6 Base 7 Seat Auto Zambezi Silver

My D3 has been wishing me 'Happy New Year' every day since New Years eve, by way of the red airbag warning light illuminating, it is now coming on within 4 mins of start up every time. Clears after a switch off and a wait, then switch on again, then reoccurs within a few mins. Phoned dealer, they told me to phone LRA, they told me to go to dealer, talk about passing the buck, its lucky its booked in next week for other things, so it's now added to the rather long list of 'to do's'.

8th Jan 2007 5:10 pm

Calcul@tor

Member Since: 08 Mar 2006
Location: Middle England!
Posts: 810

Hi - Does anyone know the TSB number that seems to refer to this fault, as mentioned by Winger above?

Thanks D4 XS MY12 Galway

9th Jan 2007 10:24 am

10forcash

Member Since: 09 Jun 2005
Location: Ubique
Posts: 16534

2007 Discovery 3 TDV6 HSE Manual Zermatt Silver

TSB is LA308-001 VIN-range: 5A300394-6A357164
"Summary:
A customer may report a concern of intermittent multiple warning lamp illumination, possibly including the hill descent control (HDC), anti-lock braking (ABS), dynamic stability control (DSC), transmission warning lamp or the "Special Programs Off" message is displayed. Investigation using diagnostic equipment reveals the diagnostic trouble code (DTC), P186D - transfer case clutch stuck, has been logged at random infrequent intervals.

Cause: When the ignition is turned on, the transfer box clutch actuator is operated through its normal range of travel to detect its relative position. If a low voltage occurs during this process, the clutch motor will stop before the end of its full range. When the voltage returns, the process begins with the motor starting from the stopped position rather than the beginning of its range. The motor will drive from the stopped position and reach an unexpected early end of range. The motor will then stall on the end stop and log the above DTC. Non-software related problems leading to the above problem, will result in permanent warning lamp illumination and a DTC logged at every ignition cycle.
Action: Should a customer express concern regarding the above, refer to the Service Procedure detailed in this bulletin to update the control module software."

Although the TSB is listed in the 'Manual transmission and clutch' section of GTR, it doesn't seem to be specific to manual transmissions

9th Jan 2007 10:35 am

Calcul@tor

Member Since: 08 Mar 2006
Location: Middle England!
Posts: 810

DND3 wrote:
My D3 has been wishing me 'Happy New Year' every day since New Years eve

I hope they sort out your problems! I'm not sure that I've still got an airbag issue - it isn't one of the warnings that came up last time! D4 XS MY12 Galway

9th Jan 2007 10:59 am

Calcul@tor

Member Since: 08 Mar 2006
Location: Middle England!
Posts: 810

Many thanks for that TFC.

I was with LRA when they first checked this problem and don't remember them referring to DTC: P186D (or more specifically, I don't remember there being any transmission or clutch related error messages), but if / when it happens again, I'll mention this TSB to the dealer.

Does anyone know whether the control module software mentioned would have been updated as part of the VEP? D4 XS MY12 Galway

9th Jan 2007 11:04 am

10forcash

Member Since: 09 Jun 2005
Location: Ubique
Posts: 16534

Yes, it should have been updated, there is another TSB that specifically mentions multiple fault warnings, this is due to the EGR / MAF sensor calibration at low temperatures so it may apply
TSB LA303-005 VIN-range: 5A300394-6A353440

Summary:
A customer may report a concern that following engine start in cold weather conditions, multiple chassis system related warning lamps are illuminated and that the air suspension is lowered to the access position. Investigation using the worldwide diagnosis system (WDS) reveal the diagnostic trouble code (DTC) P0401 - EGR Low Flow.

Cause: A software calibration/sensitivity issue exists between the exhaust gas recirculation (EGR) flow rate and mass air flow (MAF) readings resulting in an incorrect engine torque calculation signal to be recieved by the above chassis systems. The systems respond by entering a default state resulting in the above concern.
Action: Should a customer express concern regarding the above, refer to the Service Procedure detailed in this bulletin to update the engine management software.

Of course, your problem may well be due to a partially discharged battery due to multiple short journeys, this would also cause multipe 'faults' but not normally after a period of running
It could well be an issue with a wheel speed sensor or communication from the ABS unit - this will also affect multiple systems, TSB LA418-004 & TSB100-009 refer

418-004 Summary:
A customer may report a concern that mutliple warning lamps and messages are being cascaded on the message center i.e. ABS, followed by DSC, then air suspension, transmission etc. Investigation using diagnostic equipment reveals many diagnostic trouble codes (DTCs) stored in different control modules, including codes with 'P', 'C' and 'U' prefixes. In some cases in excess of fifty DTCs have been recorded, making the start point for diagnosis difficult to establish and the first DTC logged not neccesarily correcting the issue.

Cause: The complex nature of the vehicle can cause a cascade effect with a fault code logging in more than one control module. DTCs with the 'U' prefix can cascade around the vehicle control modules as invalid data, lost communication or control area network (CAN) bus faults as can be logged by each module. A fault which is local to a system and only applicable to that system is classed as a 'hard fault' (e.g. engine sensor 'P' prefix codes and suspension sensor 'C' prefix codes). A hard fault which will result in data for engine torque, engine speed, road speed etc. being invalid will then cascade around the vehicle systems as 'U' codes. The other systems then switch to default mode as designed. For example, the Dynamic Stability Control system (DSC) requires an engine torque signal to control engine power during DSC activity and so will log a fault withing the DSC control module when the cascaded 'U' code is seen. The root cause for illumination of, for instance, an ABS/DSC warning lamp can lead the technician to investigate the ABS control module first. It may not be obvious that the root cause is within the engine control module . For example, a diesel exhaust gas recirculation (EGR) fault (a hard fault local to the engine), results in the engine control module being unable to calculate 'engine torque'. This torque will be transmitted on the CAN as invalid data and will cause the ABS, DSC and air suspension to enter default mode and illuminate amber warnings because they all need engine torque data to function fully.
Action: Should a customer express concern regarding the above, refer to the Diagnostic Procedure detailed in this bulletin to help establish the root cause of the logged DTCs.

100-009 Summary:
This Bulletin gives diagnostic guidance for Controller Area Network (CAN) faults relating to the Anti-lock Braking System (ABS) Module. Follow the Service Information outlined below.
General Principles

'CAN Data Indicating a Fault' or 'Missing CAN Data'

CAN faults fall into two basic categories. These are 'CAN Data indicating a fault' or 'Missing CAN Data'.

1 . CAN Data indicating a fault is where a CAN signal is being received by an control module but it contains data that is either indicating a fault condition or is invalid because it is out of the specified range for the signal. This type of data will occur because of a specific fault with the system from where it has been sent.
2 . Missing CAN Data is where it has been detected that CAN signals are not being transmitted. Signals may be identified as missing from a particular system or, a general CAN bus failure may be identified. If specific signals are missing, the system from which the signals are missing will be identified by the Diagnostic Trouble Code (DTC) description. A general CAN bus failure can be caused by a problem in an control module but is usually an indication of a problem with the CAN bus wiring.

CAN Related Plausibility Faults

3 . Land Rover vehicles use a variety of sensors located around the vehicle. The systems relying on these sensors use plausibility checks to monitor their 'health'. For example, the health of a brake pedal switch may be monitored by checking if the brakes master cylinder pressure increases when the brake pedal switch operates. Often plausibility checks will be carried out by comparing a sensor signal to another signal that is being sent via the CAN bus. A plausibility fault is therefore not a CAN fault but in order to trace a plausibility fault it may be necessary to be aware that CAN issues could have contributed to the fault being raised. If a system shows a plausibility fault it is therefore necessary to check all sensors relating to the plausibility and the CAN communication between the relevant control modules.

Following the 'CAN Fault Chain'

4 . Complex vehicle systems such as Anti-lock Braking System (ABS) or Dynamic Stability Control (DSC) use input signals from sensors that are wired directly into the control module and from the CAN bus. These same systems also publish signals on the CAN bus so that other systems such as the Engine or Instrument Pack can use them. Many control modules on the vehicle are therefore dependent on other control modules if they are to provide fault free functionality. This dependency may cause a hard fault in one control module to shut down functionality in a second control module. The loss of functionality in the second control module may in turn knock out a third control module. The DTCs in the third control module may point only to faulty or missing CAN data in the second control module. The root cause of the problem can therefore not be solved until the chain is followed to the first control module. The first control module should contain DTCs indicating a hard fault or it may have shut down completely (in which case it would not be possible to establish diagnostic communication with it).

9th Jan 2007 11:14 am

Calcul@tor

Member Since: 08 Mar 2006
Location: Middle England!
Posts: 810

WOW!! Thanks for all of that!

A few things for them to look at (if they haven't already), although presumably some of these should already have been covered by the VEP etc.

Battery shouldn't be an issue as my standard commute to work is 35 miles each way, but might be worth looking at at some point.

When the fault occurs, it seems to show up for all sensors at the same time and I'm fairly sure it shows before I've moved. Would this rule out the ABS / wheel sensors as a possible cause?

It looks like I'll have to wait for the weather to get cold again, although it looks like being unseasonably warm until at least the weekend. Alternatively, I guess I could always move somewhere hot, or sit around here for a while longer and wait for global warming to eliminate the problem!

D4 XS MY12 Galway

9th Jan 2007 12:30 pm

10forcash

Member Since: 09 Jun 2005
Location: Ubique
Posts: 16534

if it's a transient fault, it can take several miles to show itself, hard faults will flag a fault and DTC on startup or within two minutes depending on the system.
The only way to determine the root cause is to analyse the DTC's... of course it could be something as simple as water ingress to a connector, water density (and conductivity) changes around 4 degrees celcius so I wouldn't be suprised if this were the case - DTC's are not much help in these sort of cases, good old 'manual intervention' is needed!

Engine torque output is also broadcast to several systems so a calibration issue at low temps can cause 'faults' to be flagged in systems that use this data, there have been isolated reports of some systems not being updated fully after the enhancement programme has been applied so it may be worth your dealer checking that all systems have all patches applied to the latest uplevel

9th Jan 2007 12:48 pm

Calcul@tor

Member Since: 08 Mar 2006
Location: Middle England!
Posts: 810

TFC - many thanks for your time and effort replying to my questions in such detail and also to the earlier posters, particularly Winger.

I'll let you all know how this progresses in due course, assuming it gets cold again this year - which I suspect it just might!

Now I've just got to get the wife's Renault Espace fixed after it's broken its gearbox for the second time in 48,000 miles and 3Â½ years!!!

Fortunately, the very nice (and perhaps slightly naive) chap at the Renault Stealer quoted his service manager word for word, as saying the previous Stealer who did the last 'box had "very poor workmanship", "didn't put the guide in" and that it was a "bad error" on their part! They're speaking to Renault CS.... Teach me for buying her a French car I suppose! (2 gearboxes, suspension issues, new intercooler etc etc!). D4 XS MY12 Galway

9th Jan 2007 5:43 pm

Winger
Site Moderator

Member Since: 15 Feb 2005
Location: UK
Posts: 3428

One other thing to ask yourself is whether the light show appears after the car hasn't been used for over 24 hours. The cold weather syndrome you have already noticed is made worse at startup when the heating coils spring into life...........

9th Jan 2007 10:41 pm

Calcul@tor

Member Since: 08 Mar 2006
Location: Middle England!
Posts: 810

Winger wrote:
...ask yourself is whether the light show appears after the car hasn't been used for over 24 hours.

Yes, but it has also happened after only a few hours (perhaps 4 or 5). I haven't left it in the cold for only an hour or two yet to see if that would set it off.

Until it gets cold again, I can't really do much more.

Thanks everyone for your suggestions! D4 XS MY12 Galway

10th Jan 2007 11:30 am

DN
D3 Decade

Member Since: 23 Jun 2006
Location: W.London.
Posts: 2344

ac wrote:
DND3 wrote:
My D3 has been wishing me 'Happy New Year' every day since New Years eve

I hope they sort out your problems! I'm not sure that I've still got an airbag issue - it isn't one of the warnings that came up last time!

Thanks ac, and tfc /winger for info. Just got D3 back minus the red airbag warning light now

. I know this doesn't sound like your problem ac, but just for general info, they say the fault was traced to the pass seat belt pre tensioner, but didn't elaborate too much,and didn't sound too confident when they said ' it has been replaced and tested and we think that was the problem'. Only time will tell I suppose. Hope they sort yours out ac.

13th Jan 2007 4:11 pm