Airbag light on, aircon and windows not working

[MJNewton]

Twice now on my wife's 2013 Fiesta has the airbag light come on whilst at the same time the aircon and windows have stopped working. A strange combination of events that has had me scratching my head but I think today I have got to the bottom of it and so thought I'd share it here in case others stumble across similar...

First time this happened I went out to the car, turned it on and all was fine. A DTC scan didn't reveal anything and the airbag light was off so I didn't really have anything to go on.

Fast forward a few weeks to today and it happened again. This time I got to it before the engine was turned off so I plugged in Forscan and found the following DTCs (order and layout modified for clarity):

PCM DTC - Successful DTC reading, no error codes found
OBDII DTC - Successful DTC reading, no error codes found
APIM DTC - Successful DTC reading, no error codes found
FCDIM DTC - Successful DTC reading, no error codes found
PSCM DTC - Successful DTC reading, no error codes found
HVAC DTC - Successful DTC reading, no error codes found
ACM DTC - Successful DTC reading, no error codes found
GPSM DTC - Successful DTC reading, no error codes found
ABS DTC - U0423:00-2B Invalid Data Received From IPC (Malfunction Indicator Lamp is Off for this DTC)
PDM DTC - U0423:00-2F Invalid Data Received From IPC (Malfunction Indicator Lamp is Off for this DTC)
DDM DTC - U0423:00-2F Invalid Data Received From IPC (Malfunction Indicator Lamp is Off for this DTC)
BCMii DTC - U0200:00-08 Lost Communication With Door Control Module B (Malfunction Indicator Lamp is Off for this DTC)
RCM DTC - U0253:00-0B Lost Communication With Accessory Protocol Interface Module (Malfunction Indicator Lamp is Off for this DTC)
RCM DTC - U0423:00-8B Invalid Data Received From IPC (Malfunction Indicator Lamp is On for this DTC)
IPC DTC - U300F:00-0F Ignition Input Accessory (Malfunction Indicator Lamp is Off for this DTC)

Working through this; the first 8 are all fine and whilst ABS, PDM, DDM, BCMii and RCM are all reporting DTCs I find I often get them with Forscan as I am using a hardware-modified ELM327 OBD adapter and have to flick a switch between the high- and medium-speed busses to talk to different modules - this often makes some of them unhappy which from what I have read is entirely to be expected.

It is the last two, RCM (Restraint Control Module) and IPC (Instrument Panel Cluster), that are of particular interest though:

RCM DTC - U0423:00-8B Invalid Data Received From IPC (Malfunction Indicator Lamp is On for this DTC)
IPC DTC - U300F:00-0F Ignition Input Accessory (Malfunction Indicator Lamp is Off for this DTC)

The RCM DTC could have been explained by the HS/MS switch but the MIL light being On was the giveaway - of course what other module would be responsible for the airbag light, but why? And why would the aircon and electric windows not work at the same time? Well, the IPC DTC held the clue and whilst I couldn't fathom what 'Ignition Input Accessory' actually meant I thought I'd clear the codes and see if it came back straight away. Forscan reset the DTCs and said to cycle the ignition and that's when I discovered what I think was the issue - the moment I touched the key it seemed to suddenly click into place. What I mean by that is that the ignition key has four positions: 0: Off, I: Accessory, II: On and III: Start (these are my names for each position - I don't know what the official terms are). When the engine is running the key should obviously be sitting in position II: On but I think it was sitting ever so slightly beyond that i.e. when my wife had started the car (in position III: Start) and released the key it hadn't fully fallen back to II: On.

I think that the IPC thought the key was in position I: Accessory and yet (most of) the rest of the car was clearly operating as if it was in position II: On. Because of this the IPC couldn't pass on a positive indicator to any other module that also needs to know for certain. The aircon and windows obviously shouldn't function when the car is off (and, if I'm right, that's why they weren't working) and presumably neither should the airbag module either hence the DTC due to inconsistency of inputs ('power received as if the car is on but the IPC is saying it isn't', or something like that).

This is just a working assumption but I thought I'd share my findings and, if it reoccurs, both my wife and I now know what the issue could be and so we'll make sure to see if the camlock on the car hasn't quite engaged back in the II: On position again at that particular instance as it ought to and will report back. If this is the case I don't think I'll look to 'fix' anything as whilst it ought not to happen it's no big deal that it does and probably more hassle than it's worth to repair/replace given the ease with which it can be resolved if/when it happens.

[Peter99]

My wife has the same problem on her 2014 fiesta. We returned it under warranty last year and Ford reported a defective battery that caused the ECU to resort to redundancy of these functions. I could buy into their explanation if it did not include the non functioning air bag. I purchased a new battery not from Ford as theirs was exorbitant and the problem went away. However, since the hot weather has arrived the problem has  also returned. The Ford dealer is brick walling as they always do useing warrant elapsing as the excuse. They are shortly to get a lesson in consumer rights. I was wonder what you do to correct the problem when it occurs. I have looked at how the ignition key works but it always appears  toreturn to position ii with no play or clicking when you fiddle with it. Does anyone have a ideas on this problem or the ridiculous view that Ford take that the air bag warning light on is a redundacy item. Perhaps Ford believe that I know nothing about reliability. One of the golden rules of reliability is that redundancy does not compromise safety.

[MJNewton]

5 minutes ago, Peter99 said:

I have looked at how the ignition key works but it always appears  to return to position ii with no play or clicking when you fiddle with it.

By this do you mean it is fine at the point in time when you have the airbig+windows+aircon issue? To confirm, for us it's once in a blue moon (haven't seen it for probably well over a year now despite daily usage) that we get this issue and only then that we find that the key position isn't quite set right. The rest of the time you would not know anything was wrong and so testing it without the fault present doesn't mean much.

Next time it happens, aside from giving the ignition key a bit of a wiggle I'd perform a full code scan before you turn the engine off (bluetooth adapter and smartphone will suffice - you don't need Forscan) and see what you get. The clues were there for me, albeit somewhat subtle.

[Bobr]

Many thanks for the information Matthew.   Might be very useful some time in the future.

[Peter99]

Thanks for your reply the next time my wife gets the airbag+windows+aircon fault I will ask her to make sure she keeps the engine running so that I can examine the ignition key. I was aware that you can scan the fault codes using Android smart phone or a laptop computer I just did not know how. I understand that an app and a bluetooth adaptor has  has to be purchased but am unsure what to buy. I may invest in a Forscan but it has a standard USB and my phone is a Samsung S8 and has a C type USB, I think you also have to download an App for Forscan aswell.

My wife only gets the fault when it is extremely hot weather, which persists until the weather returns to normal. She has had no trouble since the hot weather last summer until the hot weather recently. Is that what you experience? 

Do you clear the fault by turning the engine off and restarting or do you wiggle the key?

Regards Peter

[MJNewton]

19 minutes ago, Peter99 said:

I understand that an app and a bluetooth adaptor has  has to be purchased but am unsure what to buy.

eBay is full of tat, fakes and knock-offs when it comes to OBD adapters (and other things!) so I'd recommended going to Tunnelrat Electronics however I note he doesn't seem to be showing any bluetooth devices at present but I'd get in touch with him anyway.

Quote

I may invest in a Forscan but it has a standard USB and my phone is a Samsung S8 and has a C type USB, I think you also have to download an App for Forscan aswell.

Forscan is just software - you can download it for free here. It is not essential for reading fault codes though - any/most smartphone apps will do this sort of thing (Torque is popular).

Quote

My wife only gets the fault when it is extremely hot weather, which persists until the weather returns to normal. She has had no trouble since the hot weather last summer until the hot weather recently. Is that what you experience? 

To be honest I never noticed a correlation with hot weather, but I couldn't rule it out. It's been baking here recently and we haven't had the issue, but then I can't remember the last time it happened - as mentioned it could well be over a year ago.

Quote

Do you clear the fault by turning the engine off and restarting or do you wiggle the key?

I discovered the 'fix' by accident - I went to turn the ignition off and felt it click into place when I touched it. So, for us, it was just a case of rotating the key back to the 'On' position ever so slightly. It's pretty obvious when you feel it fall into place. I think what was happening was that the key position wasn't fully reverting back from the 'Start' position and thus was stuck in a bit of a no mans land causing confusion for the modules.

[Peter99]

Today the fault occured again. I managed to get to examine the ignition key with the engine running before my wife switched it off. Yureka I found the ignition key still at the iii postion and nowhere near postion ii. Just touched the key and it clicked back to position ii and the fault cleared. Ford look out I will be after a new ignition switch FOC. Thanks very much for your very informative post.

[MJNewton]

Great stuff! As annoyed a you might be (understandable) do be grateful that it's just a simple mechanical issue, and not some needle-in-a-haystack subtle electrical issue that could be virtually impossible to track down! 

[Peter99]

Yes it is a relief that my wife will be able to use her car without the airbags, aircon, windows, and fan not working. However, it just goes to show that ford dealers do not have enough knowledge of the product they sell. If it had not been for way that I am  in that I persist against all adds and that I found your post we would still be struggling with this fault. The Ford dealer who sold my wife this car when they investgated this fault laid the blame with the battery in that because the battery was down then the ecu software decided to revert to redudancy. What a load of cobblers, redundancy should not include safety critical functions such as the air bag. The thing that pisses me of the most is that they sold my wife a car with a RAC battery , not a Ford battery, and they latched on to the fact that the battery was down to explain the fault and then charged her £60 to investigate the falt as batteries are not covered by warranty. Whilst the battery was a bit down,  I purchased and fitted a new battery, The Ford one was extortionate, the old battey was given to my brother and lasted another nine months on an old series E Mercedes before he scrapped it. This battey was way under powered for this car but worked ok. I feel that we have not been treated with any consideration by the Ford dealer, they like to make a profit on your purchase and when problems arise they are only too tempted to tell you it is the way you use your vehicle, or that it is your fault or the favourite if no fault found. I do not know what I would have done unless I had found your post and I will be eternally greatfull that you bothered to publish your findings

Regards Peter P

PS I think we would have traded this car in to get rid of it without your help.

[Eric Bloodaxe]

Fascinating thread! Although I have keyless start on mine, several friends still have Mk 7.5s with keys,  so I'll bear this in mind and then may be hailed a genius if they have a similar problem in future!😀

[Yatesy1993]

Hi all, 

Sorry to drag this thread up from the grave but I have a similar issue on my 2015 fiesta st... 

Airbag light comes on - windows stop working and says hill start not available - IPC module etc on forscan too but here's the issue.... I'm keyless start! Changed battery and alternator and when this fault comes on the voltage across the battery drops from 13.5 to 12.3 essentially discharging the battery! With the smart change system unplugged the voltage drops from 14.5v to 13.5v when the fault comes on (intermittently). This only seems to happen in hot weather too, any ideas? Ford warranty keep saying alternator or battery but have changed these and same issue! 

 

Driving me mad! 

[edwin laan]

Hi al, i have the same problem with me fiesta st 2014, do any what the problem is, i have change the alternator, battery and still have this problem.

[Brandon_R]

On 11/6/2022 at 11:26 AM, edwin laan said:

Hi al, i have the same problem with me fiesta st 2014, do any what the problem is, i have change the alternator, battery and still have this problem.

Hi I also have the same problem, the cars been in the garage 9 days and they can't fix it did you find the solution 

[unofix]

7 minutes ago, Brandon_R said:

did you find the solution

...mmmmmm

That was over 9 months ago, I would expect that it's fixed by now. 🤔

[Brandon_R]

1 minute ago, unofix said:

...mmmmmm

That was over 9 months ago, I would expect that it's fixed by now. 🤔

Exactly so I'm hoping they might have a solution for me so I can tell ford how to do their job lol🤦‍♂️

[unofix]

No one has returned so you're not going to get an answer from them.

@Yatesy1993 joined 5th June 2020. Posted one question 5th June 2020. Was last here 5th June 2020

@edwin laan joined 6th Nov 2022. Posted one question 6th Nov 2022. Was last here 6th Nov 2022

Have you got push button start, or a keyswitch start ?

[Brandon_R]

11 minutes ago, unofix said:

No one has returned so you're not going to get an answer from them.

@Yatesy1993 joined 5th June 2020. Posted one question 5th June 2020. Was last here 5th June 2020

@edwin laan joined 6th Nov 2022. Posted one question 6th Nov 2022. Was last here 6th Nov 2022

Have you got push button start, or a keyswitch start ?

Damn okay thank you, yeah I have push button start but all the same symptoms. Should I make a new topic

[unofix]

46 minutes ago, Brandon_R said:

Should I make a new topic

Yes it might be a good idea. The original thread dates back to 28th April 2017 and was a car with a traditional keyswitch ignition.