Cadillac Alarm Failure After Routine Service Visit

Had a similar situation with my 2017 Caddy Life TSI. The security alarm started acting up right after routine maintenance too. Turned out the alarm sensor wiring got disturbed during the oil change service. The main symptoms matched yours, no response from central locking, alarm system would not arm properly, and the indicators stopped flashing when locking. The stored error code pointed to a communication issue between the alarm system and the central control unit. This required more than just a simple battery issue fix. The mechanic had to: Reset the complete alarm system, Recalibrate the interior monitoring sensors, Check and resecure loose wiring connections, Update the security module software The car alarm functionality fully restored after proper diagnostics and rewiring. While not a major mechanical issue, it needed specialized diagnostic equipment to properly identify and fix the communication error between modules. Worth noting that alarm sensor problems often surface after maintenance work where components near the wiring harness are accessed. Best to have it checked soon to avoid potential starting or immobilizer-related issues.

Thanks for sharing the details about the alarm system repair. That exactly matches the issues I had. Quick question, do you remember roughly how much it cost you to get everything fixed? Also, has everything been working fine since the repair? I just want to get an idea of costs and reliability before I take it to a shop, since my alarm control unit is showing similar symptoms with the central locking and sensor problems. Given how the alarm sensor issues started after maintenance in both our cases, I suspect disturbed wiring could indeed be the culprit. Just hoping it wont require replacing the entire security system.

Got everything sorted with the car alarm, paid 45€ total for fixing the security alarm system. They diagnosed the loose wiring and recoded the alarm sensor to properly trigger the indicators when locking. The central locking and alarm system have been working flawlessly since the repair. No need to replace any major components. The alarm system malfunction was directly related to the disturbed wiring during the earlier maintenance. Once they properly secured and tested all connections, the alarm control unit started communicating correctly with all sensors again. Based on the matching symptoms, you likely have the same underlying issue. A qualified shop should be able to resolve your alarm sensor problems without extensive repairs or replacements. The key is proper diagnostic testing to pinpoint exactly where the wiring got disrupted.

Thanks for the helpful responses. Just wanted to update on my situation with the alarm system failure. Finally got it checked out at a local specialist shop rather than going back to my previous mechanic. The diagnosis confirmed loose wiring connections affecting the alarm sensor, triggered during that earlier maintenance work. Total repair cost came to 65€ including diagnostic testing and rewiring. The technician found and fixed a damaged wire near the hood latch that was causing the false alarm triggers. After resetting the immobilizer and recalibrating the system, everything is working perfectly now. No more power failure warnings or unusual alarm activation. The central locking, indicators, and alarm system are all functioning as they should. Really glad it turned out to be just a wiring issue rather than needing a full alarm system replacement. Good learning experience about being careful who works on these sensitive electronic components during routine maintenance.