V40 failed MOT (Need advice)

[Hoggy32]

So I took my V40 to a regular MOT and it failed on some stuff, I managed to fix all of them (so I thought..) one of the thing was the SRS warning light was on.

This was due to a write underneath my seat cut, this is also connected to the seat belt reminder. I also found some other guy with the same issue (https://www.volvoforums.org.uk/showt...=201264&page=2)

Anyway, I removed the seat and fixed the wire. The SRS light did go away and seat belt reminder working perfectly fine. So I took it to another MOT test and they failed me on SRS being faulty this time.

So SRS light comes on on ignition and off when you start the car, but if you do this repeatedly, some times, when it's in ignition the SRS is not turned on... And they said that it should always be on when it's in ignition. I have a VIDA and there is nothing about the SRS...



Another issue I have is the handbrake not being good enough, they said left side was not good at all. How do I adjust the handbrake, is there any guide? Is there a way to determine if it's the wire or brakepad gone bad? (I did adjust the handbrake through the centerconsole which you are not supposed to do, but that didn't help it)

[ITSv40]

Poor handbrake are a common issue - most likely the handbrake mechanism in the caliper is seizing. Easy way to check, is to note the hand brake lever returns to the stop when the handbrake is off. If the lever does not move freely, it needs a new caliper. Another check is to release the cables and check that they move freely.

[SnineT]

Originally Posted by ITSv40

Poor handbrake are a common issue - most likely the handbrake mechanism in the caliper is seizing. Easy way to check, is to note the hand brake lever returns to the stop when the handbrake is off. If the lever does not move freely, it needs a new caliper. Another check is to release the cables and check that they move freely.

Good call, he might be able to un seize the caliper easy enough if it's that, if the car has an EPB take the motor off before attempting un seize protocols.

[ITSv40]

Originally Posted by SnineT

Good call, he might be able to un seize the caliper easy enough if it's that, if the car has an EPB take the motor off before attempting un seize protocols.

No EPB on our cars. Just straightforward simple mechanical.

[Simmy]

have you read the codes to find out what put on the srs message the message will always return if you have not deleted the old stored code it is possible to check all srs components with vida and dice

[Hoggy32]

Originally Posted by ITSv40

Poor handbrake are a common issue - most likely the handbrake mechanism in the caliper is seizing. Easy way to check, is to note the hand brake lever returns to the stop when the handbrake is off. If the lever does not move freely, it needs a new caliper. Another check is to release the cables and check that they move freely.

I did check the calipers today and it all seemed good, I added some silicon grease to the slide bolts for the caliper as well on the actual pads where it touches the brake caliper.


As for the SRS stuff, I did another scan and got this:
https://i.imgur.com/Dy2lLMt_d.webp?m...fidelity=grand

So I guess the module is faulty? I think it has to do with the 2 wires under the seat as I explained in the OP. Should I redo the wires, or is it 100% the SRS module that needs to be replaced?

[Hoggy32]

I took a video of the left side today when I pull the handbrake, does it look like normal or should it move even more?
https://www.youtube.com/watch?v=DJQlNpYGnNM
[YOUTUBE]https://www.youtube.com/watch?v=DJQlNpYGnNM[/YOUTUBE]

I will look the right side another day

[ITSv40]

Originally Posted by Hoggy32

I took a video of the left side today when I pull the handbrake, does it look like normal or should it move even more?
https://www.youtube.com/watch?v=DJQlNpYGnNM
[YOUTUBE]https://www.youtube.com/watch?v=DJQlNpYGnNM[/YOUTUBE]

I will look the right side another day

The caliper is seized. Although the lever is moving, which suggests the cable is free, it is not returning to its stop. With the handbrake off, the lever should sit hard against the bracket that is above the lever in the video.

Remove the caliper and wind the piston back in fully and then apply the footbrake a few times to push the piston back out - be careful not to push the piston too far. Try to dribble a little drop of brake fluid under the piston seal and rewind the piston back in fully. Do this several times until the piston will rewind freely, then reassemble on the carrier and apply the footbrake to settle the pads. The handbrake lever should now be sitting against the stop and return after the handbrake has been applied and then released.

Do both sides and you should have a good handbrake. If after all this the levers are reluctant to return to the stops, you need new calipers. the other thing to check is that the cables are adjusted correctly - I think the spec is 5-7 clicks of the lever to apply the brake. I assume you have the little tool for rewinding the caliper piston as it needs pressure applied as the piston is rotated to wind it back into the caliper. HTH.

[Hoggy32]

Originally Posted by ITSv40

The caliper is seized. Although the lever is moving, which suggests the cable is free, it is not returning to its stop. With the handbrake off, the lever should sit hard against the bracket that is above the lever in the video.

Remove the caliper and wind the piston back in fully and then apply the footbrake a few times to push the piston back out - be careful not to push the piston too far. Try to dribble a little drop of brake fluid under the piston seal and rewind the piston back in fully. Do this several times until the piston will rewind freely, then reassemble on the carrier and apply the footbrake to settle the pads. The handbrake lever should now be sitting against the stop and return after the handbrake has been applied and then released.

Do both sides and you should have a good handbrake. If after all this the levers are reluctant to return to the stops, you need new calipers. the other thing to check is that the cables are adjusted correctly - I think the spec is 5-7 clicks of the lever to apply the brake. I assume you have the little tool for rewinding the caliper piston as it needs pressure applied as the piston is rotated to wind it back into the caliper. HTH.

Sorry for late update, I did everything you said but it was still not releasing like it should. But better than before. I also think the handbrake wire needs to be replaced.

Regarding the SRS Airbag module stuff, I took the seat out, and soldered the wires properly. Then I ran the VIDA Dice and did a reset, now the airbag system works fine without any errors!


Took it to MOT and it passed