Car alarm repair

Typical complaints

• The alarm goes off at night without anyone near the car
• The alarm goes off in warm or damp weather
• The car no longer starts because the immobiliser stays engaged
• The siren keeps blaring until the battery is disconnected
• The remote control has to be held right next to the car

How a repair is carried out

Measurements are taken before anything is dismantled. Supply lines, earths, switching signals and sensor outputs are checked while the system is running, so that an intermittent fault becomes visible instead of guessed at.

Repair follows: renewing contacts, eliminating poor connections, adjusting or replacing a sensor, restoring a damaged wiring harness. Where needed, the installation is rebuilt more neatly, so the problem doesn't return within a year.

What's often the real cause

• Oxidation on terminals, splices and earth points
• Moisture in the module, the siren or a door contact
• Ageing ultrasonic or shock sensors becoming too sensitive
• Quick connectors from an old installation coming loose after years
• A weak or draining battery sending the system into fault mode

When repair no longer makes sense

Sometimes the conclusion is that repairing would mean putting money into an outdated module: parts that are no longer available, a damaged circuit board, or an installation so deeply worked into the original wiring that starting over is the tidier option. That's said before the work starts, not after.