SRS light on, B-1008 code but wiring ok - huh?

Evening all,

I lent out my D2 to a customer while I fixed his car and now it came back with the SRS light on

So gets the Lynx out and showing B-1008 Open circuit in drivers air bag - permanent

Now I have had this before so I took off the drivers air bag and shorted the connector and opened the fuse box cover

Found the Air bag wire and disconnected it and did a continuity test - seems OK

Now on my last car there was an issue of replacing the wire from the air bag under dash wire to the ECU - so I did


Still would not reset

Tried a different ECU and still the same, so I took out my jumper and fitted the air bag - still the same

This is odd as with a continuity test being fine, how can two ECUs give the same error? If the rotary coupler was bust then there would be no continuity - or is this anther land rover thing? All rest of steering wheel functions are OK

I can get continuity from the ECU through to the drivers air bag yet says open circuit

I did a web search on code 1008 but only one LR related answer (on here) but most come up with Renault problems

Mike
Canada

have you continuity through rotary coupler , usual fault is coupler when you split connectors the two wires are the connected so continuity test doesnt work as youd think

Yes I have continuity from ECU in a loop test - this is why is seems so odd to say open circuit - and 2 ECU says the same message

However - I tapped into the wires in the loom near the ECU not from the connector itself as I didn't have a pin small enough - will check in the morning

Mike

britrest said:

Yes I have continuity from ECU in a loop test - this is why is seems so odd to say open circuit - and 2 ECU says the same message

However - I tapped into the wires in the loom near the ECU not from the connector itself as I didn't have a pin small enough - will check in the morning

Mike

Click to expand...

what i meant was when you disconnect coupler the connector joins the 2 wires

If I disconnect the coupler at both ends (air bag itself and connector under dash) then jump the air bag connector with a jump wire, then I get continuity at the red plug under the dash

I have not checked if there is continuity without the jumper - I know there is resistance in the air bag itself

http://www.landyzone.co.uk/lz/f8/srs-warning-light-fault-code-b1008-203607.html

http://www.rhobbs.co.uk/2012/03/land-rover-rotary-coupler-internals-close-up-photos-yrc100350/

let everything connected, use some sewing needles if you can't insert the multimeter's terminals and check directly in the ECU plug's pins with plug disconnected... it's not enough to be continuity, the airbag's resistance is around 2.5 ohm(i didnt find a clear data about that for D2, only for othetr cars), if the resistance is higher the ECU will interpret it as open circuit, eventually compare with the passenger's airbag resistance(also at ECU plug) use only digital multimeter with low voltage output on resistance otherwise there's the risk to blow the bag, the most certain way to check this thing is to unplug the airbag and use a 2-2.5 ohm resistance instead of it...if you get rid of the fault code this way the problem is the airbag itself(that's why they recommend them to be replaced after 10 years as they loose theyr qualities), that's why these are used Universal Air Bag Fused Resistor Kit 2.2 Ohm X1, Removal, Delete New | eBay

i'll tell you in my rotten english what jamesmartin was trying to tell you: the airbag's plug has a spring type bypass in it which closes when you unplug it to protect it from deployment in the eventuality of external feed.

hope this helps

Sorted!

It was indeed the rotary coupler

Didn't realise they are the same as a D1 so I had a few on the shelf - mind you I had to junk 2 before I found one that worked with all functions on the steering wheel

Many thanks - there is one for the record!

Mike