U0168: Communicatieverlies met de regelmodule alarmsysteem
Wat te doen
The alarm has stopped working properly. The car still starts and drives — that is the immobiliser, which is a different system.
Two things can happen, and one of them is much more annoying than the other.
The alarm may simply not arm. The car locks normally, but nothing is watching it. The clue is that the usual flash or chirp when you lock is missing — worth knowing before you leave it somewhere you would rather not.
Or it may go off by itself, usually at three in the morning. When the alarm computer stops hearing from the modules watching the doors, the bonnet and the boot, it cannot tell a real opening from a lost message — and an alarm's safe assumption is that something happened.
If that is what yours is doing, ask for the bonnet switch to be checked first. It is by far the commonest cause of alarms going off on their own: it sits in the engine bay, it corrodes, and it gets knocked out of adjustment by washing and servicing. It is also cheap.
One warning: do not try to silence a going-off alarm by disconnecting the battery. The siren has its own internal battery precisely so that this does not work, and on many cars disconnecting sets it off. There is a proper disarm procedure — ask for it rather than forcing it, because a siren forced into protection mode may have to be replaced.
Wat deze code betekent
The vehicle security module has stopped being heard from. The general reasoning is at U0100, and U0427 covers the same module reporting implausibly instead.
This is the alarm rather than the immobiliser, and separating the two saves a great deal of confusion. The immobiliser at U0167 stops the vehicle being driven; the alarm at this code makes a noise and flashes lights. A vehicle with an alarm fault normally still starts and drives.
Silence here fails in two opposite directions, and the second is what brings people in.
It may not arm at all — the vehicle locks, nothing is watching it, and the only way to know is that the usual confirmation flash or chirp is missing. Worth knowing before parking somewhere you would rather not.
Or it may go off by itself, repeatedly, usually at night. A security module that has lost contact with the modules watching the doors, the bonnet and the boot cannot tell a genuine opening from a lost message, and the safe assumption for an alarm is that something happened. That is the version that makes a car unwelcome where it is parked, and it is worth treating as urgent for social reasons rather than mechanical ones.
Two practical facts about alarms that people are rarely told.
The siren usually has its own internal battery. Disconnecting the vehicle's battery does not silence it — that is the point of it — and on many designs doing so triggers it. There is normally a documented disarm procedure, and forcing the issue can leave a siren that has to be replaced.
And the bonnet switch is the leading cause of self-triggering alarms by a wide margin. It lives in the engine bay, it corrodes, and it gets bent out of adjustment by every wash and every service. It is cheap and it is the first thing to look at.
Waarschijnlijke oorzaken
Begin hier
- Gecorrodeerde of losse stekker · eenvoudig
- Ondeugdelijke montage van alarm of startonderbreker · gemiddeld
- Zekering doorgebrand of voeding uitgevallen · eenvoudig
- Water binnengedrongen in de module · gemiddeld
Minder vaak
- Bedrading van de databus beschadigd · gemiddeld
- Lage systeemspanning · gemiddeld
Symptomen
Betrokken onderdelen
Informatie, geen instructie
CarGeek is een naslagwerk, geen werkplaatshandboek. De pagina's zijn geschreven op basis van openbare bronnen en van wat anderen hebben ondervonden, nooit op basis van de servicedocumentatie van de fabrikant zelf, dus ze kunnen onjuist of onvolledig zijn voor jouw specifieke voertuig. Een deel van wat erin staat brengt echt gevaar met zich mee: hoogspanning, brandstof onder druk, opgeslagen energie en hete of bewegende delen.
Laat alles waarnaar je wilt handelen eerst controleren door iemand met een technische opleiding, aan de hand van de eigen procedure van de fabrikant voor jouw voertuig. Niets hier vervangt die procedure.
Ervaring uit de community
Wees de eerste die dit beschrijft
Hierover is nog niets geplaatst. Wat je ook hebt gevonden, het is het opschrijven waard — zelfs een doodlopend spoor bespaart iemand dezelfde middag.
Wat het de moeite waard maakt:
- De auto — merk, model, bouwjaar en motor. Dezelfde storing gedraagt zich per auto anders.
- Wat je gemeten hebt, niet alleen wat je vervangen hebt.
- Wat het echt verholpen heeft — of dat niets dat deed, wat ook nuttig is om te weten.
Inloggen of een account aanmaken om toe te voegen wat je hebt gevonden over U0168.