SRS Dash Light Staying On....

[Tikka7mm08]

Son's truck did some river crossings and after drying it for a while the SRS light is on. Used contact cleaner on the yellow pretensioner plugs under the seat, no joy.

Fault code 0x90. Can see the SRS module under the cubby box. Looks a mission to get to....before looking to replace is there anything else I should first try?

[sierrafery]

....Fault code 0x90.... That doesnt mean too much, read the code with a dedicated scanner which gives you a clear description of the fault and reveal that

[Tikka7mm08]

I'll try again... I cleared the codes to see if it was fine, before realising it self-tests and will stay off if AOK.

[Tikka7mm08]

Ok - my son says the faults are on the left and right pre-tensioners, failure at ignition and failure to ground. Sounds like the module under the cubby box?

[sierrafery]

Clear the codes, unplug both pretensioners and read again... if the codes dont change in open circuits then the DCU becomes suspect

[Tikka7mm08]

Clear the codes, unplug both pretensioners and read again... if the codes dont change in open circuits then the DCU becomes suspectSo read while unplugged?

[sierrafery]

Yes, to check if the DCU reacts well or not

[Tikka7mm08]

Update. He cleaned the ground on one pretensioner and it has come right so he is trying the one with ignition fault code clearing, unplugging and reading.

[Tikka7mm08]

Update, the unplugged ignition fault pretensioner returns open circuit fault... so if reading open circuit DCU is AOK and replace the pretensioner?

[Tikka7mm08]

Pretensioner is running 2.3 ohms so is ok. Squirting contact cleaner in and testing again plugged in.

[Tikka7mm08]

Now the 0x90 fault is back, pretty sure it is the DCU.

[Tikka7mm08]

Final update, son managed to unplug DCU and sneak mum's GHD air dryer out to the workshop. Worked fantastic he said and all put together the SRS light is off joining the demise of the 3 amigos by fitting a new abs sensor. Yay.