<![CDATA[Volvo V40 SCL/SCU Pairing]]>'Steering lock try start again.'

My car is immo locked with this message on display.

I bought a new SCL but unable to pair via Vdash, the command wont execute.

So I bought a new IAU (immobilizer antenna unit) thinking this is the SCU, but even a new virgin unit produce error during pairing, saying the SCU already programmed.

My v40 is P3 keyless model, and its SCU slightly different than previous generation volvos, in one picture, it shown the SCU as a combination of 3 parts; a push start ignition switch, a plastic frame and an IAU (immobilizer antenna unit).

But in the official wiring diagram, the SCU and IAU are two different parts, as connected in the car starting circuit.

Please advice whether the ignition switch itself is the SCU that requires pairing to the SCL. And whether the IAU also requires programming.

Anyone?

]]>https://forum.d5t5.com/topic/301/volvo-v40-scl-scu-pairingRSS for NodeSun, 19 Apr 2026 09:18:56 GMTMon, 13 Apr 2026 04:58:05 GMT60<![CDATA[Reply to Volvo V40 SCL/SCU Pairing on Tue, 14 Apr 2026 13:25:55 GMT]]>After doing some research in VIDA, I found out that this car doesn't seem to have a SCU. Instead everything related to the IMMO/starting the engine is handled by the KVM. This would mean no coding possible with Vdash unless you have the KVM pin which can't be cracked by Vdash. VIDA states an IAU reload is needed after changing the IAU. Start button and iginition switch don't need any software after replacement.

]]>https://forum.d5t5.com/post/1001https://forum.d5t5.com/post/1001Tue, 14 Apr 2026 13:25:55 GMT<![CDATA[Reply to Volvo V40 SCL/SCU Pairing on Tue, 14 Apr 2026 09:43:48 GMT]]>I think that 1215 is related with inability to unlock the IMMO and therefor to perform any codding. I`m receiving the same when trying to decode the IMMO in order to add new key.

]]>https://forum.d5t5.com/post/1000https://forum.d5t5.com/post/1000Tue, 14 Apr 2026 09:43:48 GMT<![CDATA[Reply to Volvo V40 SCL/SCU Pairing on Mon, 13 Apr 2026 15:55:29 GMT]]>@pamie849 The switch you ordered is just that. A dumb switch and a part of the SCU. The programable part is the one I have posted above (31252952). The whole SCU looks like that according to EWD 121141.png
Continuity doesn't mean there is actually communication between the ecus. You would need an oscilloscope to check that.

What error 1215 means is beyond me. You will need to ask the guys from D5T5 about that.

]]>https://forum.d5t5.com/post/997https://forum.d5t5.com/post/997Mon, 13 Apr 2026 15:55:29 GMT<![CDATA[Reply to Volvo V40 SCL/SCU Pairing on Mon, 13 Apr 2026 13:32:11 GMT]]>do you know about read error: 1215 above?

]]>https://forum.d5t5.com/post/996https://forum.d5t5.com/post/996Mon, 13 Apr 2026 13:32:11 GMT<![CDATA[Reply to Volvo V40 SCL/SCU Pairing on Mon, 13 Apr 2026 13:26:26 GMT]]>@T5-T6-Schnappi

ECM-U016700 Lost Communication With Vehicle Immobilizer Control Module.

This is what originally shown when it first happen.

I checked all fuses, they're ok.

I also did continuity test from all wirings from SCL, IAU, Push button switch to CEM. Also ok.

virgin SCL wont pair to SCU.

virgin IAU pairing produced error, as above.

I just ordered new push button switch, but I dont know if its really programmable, but this site here tells it is. https://www.ipdusa.com/products/13636/Start-Stop-Engine-Button-Switch-Mid-P3-Genuine-Volvo-31456644-31318791-31394113

]]>https://forum.d5t5.com/post/995https://forum.d5t5.com/post/995Mon, 13 Apr 2026 13:26:26 GMT<![CDATA[Reply to Volvo V40 SCL/SCU Pairing on Mon, 13 Apr 2026 10:20:17 GMT]]>@pamie849 The SCU is nr. 1 in this diagram. https://volvoparts.barrybourke.com.au/a/Volvo_2015_V40-25l-5-cylinder-Turbo/_51513_12294337/Ignition-switch/GR-367012.html

What exact DTCs do you have, and did you check all fuses?

]]>https://forum.d5t5.com/post/993https://forum.d5t5.com/post/993Mon, 13 Apr 2026 10:20:17 GMT<![CDATA[Reply to Volvo V40 SCL/SCU Pairing on Mon, 13 Apr 2026 05:05:24 GMT]]>0.jpg failure to pair new virgin IAU

]]>https://forum.d5t5.com/post/992https://forum.d5t5.com/post/992Mon, 13 Apr 2026 05:05:24 GMT<![CDATA[Reply to Volvo V40 SCL/SCU Pairing on Mon, 13 Apr 2026 05:03:03 GMT]]>11.jpg Ignition switch. Design is simple, like a mechanical switch, but there is small circuit board inside.

]]>https://forum.d5t5.com/post/991https://forum.d5t5.com/post/991Mon, 13 Apr 2026 05:03:03 GMT