The Honda CR-Z is a sporty compact coupe that was offered from 2010 to 2016.
Despite its style and performance, the CR-Z can be prone to certain alarm issues.
If your CR-Z keeps going off, you have come to the right place.
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Why Does My Honda CR-Z Alarm Keep Going Off?
A Honda CR-Z alarm is usually triggered by a faulty hood switch or door switch as these sensors are prone to defects or damage (over time). Other common causes include a drained 12V battery, key fob issues, water leakage, and a failing Anti-Theft System.
1. Faulty Hood Switch
A faulty hood switch is a common cause of unwanted alarms for Honda vehicles (CR-Z included).
The switch is typically embedded in the hood latch.
The small electronic device is designed to detect whether the hood is open or shut and is an important part of the car’s alarm system – if it is broken, loose or dirty it can send false readings to the car’s computer thus triggering the alarm.
- Pop the hood and locate the hood switch.
- Check for any obvious damage, rust or loose connections.
- Give the hood switch a clean too (use contact cleaner), as dirt and grime can cause issues.
- You can test the switch with a continuity tester.
If you are well-versed mechanically, you can buy a new hood switch online and replace it yourself. Otherwise, we’d advise visiting your local mechanic.
On CRZForum.com, we found these comments by owners:
“Might be the sensor/switch for the Hood(bonnet) latch. You’ll need to do a forum search, but it has been an issue that has been discussed. Hope that helps.”
“I had a similar problem and it was in fact the hood sensor. I just unplugged it and the problem went away and never came back.”
“Unplug the electrical connection for the hood latch that usually causes the alarm to keep going off.”
One owner on the r/CRZ subreddit mentioned this:
“I have had my 2014 manual for a year and a half, did have one issue. The alarm would go off for no reason, traced it back to a bad sensor on the hood latch. Outside that, been a fun ride so far.”
2. Malfunctioning Door Switches
Faulty door switches (including the rear hatch) are another common cause of random alarms on the CR-Z, similar to the hood switch, these switches monitor the open/closed status of the door – if damaged, faulty or dirty they can send false readings thereby triggering the alarm.
Door switches are a common point of failure as they are subject to wear and tear due to the doors being continually opened/closed/slammed etc.
The door latches and door switches can get dirty too which can cause issues, so the first thing you should do is give all door latches a good clean and spray some WD-40 on the latch and work it in to see if that helps.
Also check the wiring leading from the body into the door for any signs of damage, it should be in a flexible hose on the hinge side of the door.
If you suspect the alarm issues are linked to the door switch, ask your dealer to run a diagnostic test to try and pinpoint the fault.
We found these tips from owners on CRZForum.com:
“Hi I had the exact issue with my 2011 CRZ, alarm going off randomly, lights not flashing when setting the alarm with the key fob. I simply opened each door, pressed the door sensors, the same on the bonnet and boot and this resolved the problem.”
“Maybe a bad contact on the sensor door or back door. Try to clean contact.”
3. Drained 12V Battery
A faulty or weakened car battery causes a variety of problems, including accidentally triggering the CR-Z alarm.
The best thing to do is take your CR-Z for a battery health check, these are usually quite inexpensive or sometimes free such as at AutoZone.
Or you can test it yourself with a multimeter (see the guide at the end of this article).
A healthy 12V battery should be about 12.6 to 12.8 volts while a weakened battery reads below 12 volts.
On CRZForum.com, this was shared by an owner:
“We have lots of postings about this issue. The alarm switch that is part of the hood latch has failed or your under hood battery is weak. Unplug the switch and have the battery load tested.”
Over at the r/Honda subreddit, we found this comment:
“Maybe a dying battery? A bad battery can cause all sort of strange problems from my experience.”
4. Loose or Bad 12V Battery Connections
Loose or bad 12V battery connections can cause a number of problems, including triggering the alarm of your CR-Z.
A bad connection can be caused by dirt or gunk buildup.
The terminals may have come loose from driving and vibrations etc.
Make sure the engine is off before doing any work on the battery.
- Inspect the battery and look for any signs of damage, dirt build-up, rust, or corrosion.
- Disconnect the battery and loosen the nuts on the clamps using a wrench.
- Remove the negative clamp, marked with a “-” first.
- Clean the terminals with a toothbrush dipped in a mix of baking soda and water, rinse with distilled water and dry with a cloth.
Reconnect the battery, ensuring tight connections.
5. Water Leakage
Water leaking into the latches and sensors is quite common for owners of the CR-Z. It is essentially a design flaw that can trigger the vehicle’s alarm.
While the quick fix is to wipe down vulnerable areas around your latches and switches, it would be much better to consult with auto mechanics to find a long-term solution (such as adding additional seals or rubber linings).
Here is what one owner had to say on CRZForum.com:
“I also had this happen when I had some water leak into the rear latch mechanism. It gets in through the top of the vertical window. Eventually the latch went south, but you can prevent the water ingress by lining the top of the vertical window with rubber heat shrink tubing. You’ll know if this is your issue as when you open the boot after its rained water will pour out of the latch.”
6. Failing Anti-Theft System
If your car has notified you that your Anti-Theft System has malfunctioned, then it is likely that this is related to your alarm going off.
This is what one owner on the r/CRZ subreddit shared:
“Sounds to me like it’s in some kind of anti-theft immobilizer mode. You could try to reset the immobilizer by putting the key in the driver door, turning to unlock, then lock, then unlock again. Not sure if that works on the CR-Z, but it seems to be a common fix on a lot of other Hondas.”
7. Key Fob Running on Low Battery
A common cause of mysterious alarms on the CR-Z is a low key fob battery. Similarly, if the fob is dirty or dusty this can also cause alarm issues.
Give the inside of your fob a clean and replace the battery to eliminate this possible cause. It’s worth spending a bit extra for a good brand of battery.
- To open your key fob, stick your prying tool into the slit or gap between the two halves of the outer casing and gently apply upward pressure to pop open the device.
- Remove the battery.
- Give the key fob a good clean to remove any dirt or fluff – a cotton swab and some rubbing alcohol should do the trick.
- Check for damage, rust or loose connection (you may need a new key fob depending on what you find).
- Be sure to insert the new battery facing the right way up.
- Assemble the outer casing of your key fob by clamping them back together.
8. Faulty Key Fob
Another reported cause of nuisance alarms on the CR-Z is a faulty key fob.
If you have 2 remotes, try taking the battery out of one and use the other for a while.
If the alarm problems persist, and you have tried cleaning the inside of the fob(s) and changing the battery, the best thing to do is speak with your dealer.
9. Rust and Corrosion on Door and Hood Latches
Rust and corrosion can also damage the latches and switches, which may trick the sensors into detecting that a door or the front hood is open.
If your car is frequently exposed to moisture or other external elements, then you should routinely inspect critical areas of your vehicle for any sign of rust or corrosion.
A simple yet effective solution is to lubricate your car’s hinges just to provide a layer of protection against rust-causing agents.
10. Incorrectly Installed Aftermarket Alarm
An incorrectly installed or faulty aftermarket alarm system is a common cause of nuisance alarms.
Aftermarket alarms are typically far more complex than any factory-installed equipment which makes them more prone to issues.
They may also have been installed by incompetent individuals.
If you are experiencing issues with an aftermarket alarm, the best thing to do is speak with a reputable auto electrician.
11. Damaged Wiring
Damaged electrical wiring can cause a wide range of problems, it can often be tricky to pinpoint too and you may need to have an auto electrician run some diagnostic tests.
12. Animals Climbing On The Vehicle
If your alarm has been set off in the middle of the night, it may have been by an animal climbing on the car.
States such as Illinois, Indiana, Iowa, Texas, Wisconsin, and Carolina have large wild raccoon populations.
Have a look for footprints on the hood and the roof.
If you have a CCTV system, examine the footage. These animals usually appear during the night.
13. Not Closing Doors, Hood, or Trunk Properly
Something as simple as not properly closing the doors, hood, or trunk will inevitably trigger the alarm.
Make sure to check if you have closed every point of entry of your vehicle to avoid accidentally tripping your CR-Z’s alarm.
Check for Recalls or TSBs
By entering your car’s VIN number on Honda’s recall page or the NTHSA’s Safety Issues & Recalls page you can determine whether or not there is a TSB or recall for your vehicle and if there is you’ll want to get it addressed.
A recall is issued by a vehicle manufacturer for issues that are safety-related, while a TSB covers components that may be malfunctioning but don’t compromise the safety of the vehicle.
Disconnect the Battery
Sometimes mysterious alarm problems can disappear with a simple reboot, there are no guarantees here but it’s worth a try.
Disconnect the battery for 20 seconds and this resets many of the electronics in the vehicle.
Check For Warning Messages
When the alarm occurs can you see any lights or warning messages on the instrument panel?
This can give a clue as to what’s causing the alarm e.g. ‘Hood Ajar’.
Take it to a Honda Dealership
If needed, take your Honda to the dealership.
Tell them you are NOT paying for a check on what the problem might be.
Ask them if they will check it for free.
Most dealerships and other places do quick/initial diagnosis for no money as they plan to make money for the repair of your vehicle.
If your unit is still under warranty then they should fix and resolve the issue for free.
How to Test the 12V Battery
How to Test the Battery:
- Before testing, remove the surface charge from the battery, this allows for an accurate reading.
- Simply turn on the headlights for 2 minutes then turn off.
- Set the multimeter dial to the ’20 Volts’ setting.
- Make sure the car is turned OFF.
The multimeter will have a red probe and a black probe.
- The red probe is for making contact with the positive terminal.
- The black probe is for making contact with the negative terminal.
Measure across the battery terminals.
- The meter should display a reading, if the battery is fully charged the voltage should be between 12.2 and 12.6 volts.
- Anything under 12V and the battery should be charged or replaced.