Struggling to locate airbag crash sensor

[Fez100]

The SRS airbag warning light recently started showing on the dash of my 2002 MK4 Fiesta Ghia (1.6 Zetec-SE) and I have used a FORscan diagnostics tool to see that the fault code is:

B1342 - ECU internal fault

Module: Electronic Crash Sensor

I assume this means the airbag crash sensor is the source of the fault, and so this would either need replacing, or the terminals would need cleaning as these are apparently susceptible to corrosion (as mentioned in this other forum post: https://www.honestjohn.co.uk/forum/post/index.htm?t=65509). 

From other forum posts and a few technical pages I found online, it appear this crash sensor for my model of Fiesta is somewhere attached to the front panel, by the radiator. However, today I removed both headlamps, grill, and bonnet latch with cover and I spent around 2 hours scouring this area with a torch and could not for the life of me find the crash sensor. I did find an electrical connector/switch by the top hose of the radiator, with violet/yellow and black/yellow cables which is the same as what my Haynes manual specifies in the airbag module wiring diagram, however, I followed these cables and they lead to the bonnet catch and so I think they are to detect when the bonnet is shut, not related to the crash sensor.

Does anybody know precisely where I can find the airbag crash sensor in my Fiesta MK4 2002? I presume there is only one sensor, and that it's located in the front panel behind the bumper, and not in the side doors, but please correct me if you think otherwise. Thank you for any advice or diagrams you can provide - I really appreciate any help.

[unofix]

If I remember correctly the crash sensor or your model is in fact mounted on the bonnet latch plate.

In fact there could well be two connectors on, or very near the bonnet latch, one for the alarm/bonnet open light and the other is the crash sensor. It's easy enough to test, just unplug them one at a time and see what warnings you get.

[Dan62]

For models built up to 2002 the crash sensor is an internal component of the Air Bag Module which is located in the centre console area.

[Fez100]

26 minutes ago, Dan62 said:

For models built up to 2002 the crash sensor is an internal component of the Air Bag Module which is located in the centre console area.

For reference the reg. is LC02 LFL - this is a 2002 and so would it fall under what you are talking about? 

[Dan62]

2002 was a model change year, up to 2002 (2000-2002) the crash sensor is as I've stated.

2002-2008 its at the front of the vehicle (where you've looked and can't find it!)

Reg No. and MK's don't really help especially as there is conflict about MK's for Fiesta depending where you look.

Locate the module, if it has an arrow on it showing forward facing direction, its because the sensor is internal.

 

[Fez100]

In the 2000-2002 case you mentioned where the crash sensor is internal with the airbag control module, are there any other crash sensors located in the side doors? I have seen a technical manual for the 2004 onwards fiesta (https://workshop-manuals.com/ford/fiesta_2002.25_11.2001/mechanical_repairs/5_body_and_paint/501_body_and_paint/501-20b_supplemental_restraint_system/description_and_operation/air_bag_and_safety_belt_pretensioner_supplemental_restraint_system_(srs)_vehicles_built_from_11-2004/) which uses an internal crash sensor with airbag module, as well as crash sensors in the passenger and driver doors by the B-pillar...is this also the case for the 2000-20002 models?

I will look at the airbag control module today and check for the alignment arrow you mentioned - thanks for your advice on this!

If it turns out the crash sensor is with the module as you suspected, what would be the best course of action to clear the fault "B1342 - ECU internal fault,

Module: Electronic Crash Sensor" ?

I will unplug, clean, and re-plug all connectors first, but if this still doesn't clear the fault, should I replace the entire airbag control module? Thanks

 

 

[Dan62]

The fix for DTC B1342 is to replace the airbag control module and clear the DTC's

Sensors and airbag configuration is feature dependent I can't tell you what you have other than if it was a side sensor you would have a different DTC

Look here for for your vehicle

[Fez100]

3 hours ago, Dan62 said:

The fix for DTC B1342 is to replace the airbag control module and clear the DTC's

Sensors and airbag configuration is feature dependent I can't tell you what you have other than if it was a side sensor you would have a different DTC

Look here for for your vehicle

Wow that's a great page - very comprehensive! Shame there doesn't seem to be an equivalent SRS page for the 2002-onwards models so I can check what the fault code means on those models and what the corrective actions might be. Anyway, for now I will assume my car falls under the upto-2002 category and so I'll take a look at the airbag control module when I get it back from the garage later today. 

Do you know if this module is located above the passenger glove compartment in the dashboard, or is it located under the centre console by the gear stick? It appears the former applies to models up to 1999, but I can't find any information for post 1999 models on the workshop manuals page. Thanks

[Fez100]

I've attached some photos I took yesterday around the front bumper / a frame when looking for the crash sensor. Is it possible that the crash sensor could be one of the little black boxes shown in the final photo, View B? To me it looks just like one sensor, likely to detect the bonnet opening/closing, but I am no expert by any means.

Please let me know what you think...could the crash sensor be here in the front of the car?

Sorry to keep asking about this, but I won't be able to check the airbag control module for the alignment arrow until later tonight, and so for now I thought I might as well get your guys' opinions on the front area of my fiesta. Cheers 🙂

[Dan62]

All the information you need is on the link I sent, use the "Next Page >" button to scroll forward or the "<Prev Page" button to go back. There are buttons at the top & bottom of the page being viewed but sometimes, usually the buttons at the bottom of the page are obscured or blocked by ads.

Same applies to the link you posted, page forward or back from that to find 2002.25 info. BTW from the pics you posted you have 2000-2002 model.

Up to 1999 the module is behind the glove box, yours will be here, I did the scrolling for you!

[Fez100]

On 12/8/2021 at 3:56 PM, Dan62 said:

All the information you need is on the link I sent, use the "Next Page >" button to scroll forward or the "<Prev Page" button to go back. There are buttons at the top & bottom of the page being viewed but sometimes, usually the buttons at the bottom of the page are obscured or blocked by ads.

Same applies to the link you posted, page forward or back from that to find 2002.25 info. BTW from the pics you posted you have 2000-2002 model.

Up to 1999 the module is behind the glove box, yours will be here, I did the scrolling for you!

I didn't realise there were hidden pages not listed on the side-menu! That's great, has everything I needed to know.

I've located the airbag control unit finally! You were right, it has the integrated crash sensor and alignment arrow on it, located just forward of the gearstick under the centre console. I've just ordered another one off eBay and will replace it at the weekend, then hopefully the fault code can be cleared once and for all!

Thanks again, I really appreciate your help 🙂

[Fez100]

Do you know if I can simply unplug the old module and plug in the new one I've ordered, or is some programming/formatting involved? I hope it can be a simple swap 😬

[Fiesta st150 owner]

Hi, I just had a question about the internal impact sensors system. Does that mean that there is no sensor in the front? So when replacing airbags, i should only replace the module and call it a day?

[unofix]

On 12/8/2021 at 10:16 AM, Dan62 said:

2002 was a model change year, up to 2002 (2000-2002) the crash sensor is as I've stated.

2002-2008 its at the front of the vehicle (where you've looked and can't find it!)

Reg No. and MK's don't really help especially as there is conflict about MK's for Fiesta depending where you look.

Locate the module, if it has an arrow on it showing forward facing direction, its because the sensor is internal.

According to the information above you do have a front crash sensor.

To install, reverse the removal procedure.

NOTE:New air bag control modules supplied in service require configuring following installation. Configure the air bag control module. For additional information, refer to WDS/FDS 2000.