Nowadays, the stop/start unavailable issue has become a nightmare for a lot of Jeep drivers. Many complain about the stop/start system being unavailable and getting warning messages like “stop/start unavailable service stop/start system.” Typically, battery-related issues, electrical issues, extreme weather conditions, or incompatible engine/cabin temperatures are the leading causes of this particular problem. Keep reading to learn more about why the stop/start system becomes unavailable and how to fix it.
Table of Contents
What is the “Stop/Start Unavailable Service Stop/Start System”? – Error Explained!
If you have an error message in the instrument cluster that says – stop/start unavailable, service stop/start system – it means your start/stop system is disabled due to a problem. You can also see a yellow warning light that looks like a capital “A”. You may need to service the stop/start system or fix the problem that is causing the system to be disabled.
It is perfectly normal to get a warning that your stop/start system isn’t working when you start the car. But it goes away once the engine is warmed up or the battery is fully charged. Then the stop/start system resumes automatically.
However, if the warning continues, you may have a problem. Finding and fixing the problem is essential.
For the system to function correctly, several requirements must be satisfied. There are often issues that fail to satisfy those requirements, causing the system to not work as intended. We’ll go over the most common problems here.
Keep in mind that you don’t need a functioning stop/start system to drive your Jeep. There is no problem driving without it. However, it won’t be fuel efficient or environmentally friendly.
What Causes the “Stop/Start Unavailable Service Stop/Start System” Error? What’s the Solution?
The main computer controls your stop/start system. It decides whether to make the system available or not after receiving data from various sensors and components. The system won’t work if any parameters are outside the acceptable range. The ECU will tell you to service the system.
The most likely reasons for your stop/start system being unavailable are:
- If the stop/start system suddenly becomes unavailable, chances are your battery is losing efficiency. If the battery is dying, it may not be able to start the engine repeatedly. As a result, the ECU momentarily disabled the system to ensure that the Jeep starts without interruption because the battery’s main function is starting the engine.
- Additionally, a red battery light in the upper left corner of your screen indicates a malfunctioning charging system and most likely has low voltage. If your charging system isn’t functioning, the stop/start will be disabled to ensure fundamental systems keep functioning uninterrupted.
If you see the warning that the stop/start system is unavailable, drive until the battery is full and the system should become available again.
- Check the charge levels of your main and auxiliary batteries separately if you see the warning on the screen. Charge the batteries separately if they are not fully charged. Once the batteries are fully charged, the error message should go away.
- Check the voltage. The voltage across the terminals of a fully charged battery should be between 12.5 and 12.6 volts when the engine is off. Between 13.7 and 14.5 volts when the engine is running and the alternator is recharging the battery. If something drains your batteries, disconnect them and charge the batteries to 100% separately. After checking the voltage, wait for a few hours, then recheck the voltage. A small voltage drop may occur over a few hours, but if one battery’s voltage drops noticeably more than the other, you have a bad battery. Get a digital meter if you don’t already have one; prices range from $5 to $20.
- To find a code, connect an ODB reader and run a diagnostic. If a battery-related error code appears, changing the main or auxiliary battery will resolve the stop/start unavailable error and bring the system back online. Under the front passenger seat, next to the primary 12-volt battery, is where the auxiliary battery is located.
- Corrosion or a loose connection to the battery terminal triggers this problem. If your battery terminals are corroded or there is any loose connection to the ground wire, the system does weird behavior sometimes.
All your confusion will resolve if you load test your batteries, which is typically free at auto parts stores. If you receive the error message even though your batteries are still relatively new, it’s possible that you initially received a faulty one.
Be careful. If you know your battery is gone but do not immediately disconnect or replace it, then your other battery will deplete, and you won’t be able to start your car as a result. Then you’d have to replace two batteries instead of just one.
The service stop/start warning can result from several triggers.
- A faulty hood switch can cause this. Ensure the hood switch is working correctly.
- Many people have experienced strange problems due to loose or blown fuses. Make sure that each fuse is seated correctly and they are not blown.
- Sometimes poor relay connection can cause this. Check to see if one of the stop/start system relays has a bad contact.
- Some fault codes can prevent stop/start from working when they are stored in the PCM. Clear all the error codes.
The stop-start function becomes unavailable if the outside temperature is too high or too low. In that case, the battery requires too much power to run the climate control system. The comfort settings selected by the driver determine when and if this occurs.
Sometimes the air conditioning system is automatically reduced while the stop-start system functions.
When it’s cold outside, you need to give your vehicle enough time to increase the temperature. If you do, the stop-start system will turn on once the engine is adequately warmed up. Until your computer dashboard alerts you that your stop-start system is ready, you must wait while your car warms up.
- If the engine temperature is too low, the main computer detects this. In this circumstance, the Stop/Start system becomes disabled because repeatedly starting the engine and shutting it down isn’t ideal. Hence the stop/start unavailable error appears.
- When the car stops at traffic lights, the airstream is either insufficient or nonexistent. So the radiator fan must cool the engine when it becomes too hot. The stop/start function becomes unavailable when the fan consumes a significant amount of current.
- The system can become unavailable if the cabin temperature doesn’t reach or exceeds the optimal range. It is one of the requirements for the system to be operational. When the cabin temperature reaches the optimal range, the system should resume function.
- A potential problem could be loose gas cap. Ensure that it is fixed in place.
- A damaged solar sensor, the small sensor above the dashboard, can also cause a warning. Fix it to resolve the issue.
- If the HVAC control module malfunctions, it is impossible for the system to determine whether the cabin temperature is too high or too low. The stop/start system can become unavailable.
- You might have a broken sensor. Replace it, and the start/stop will work. If you’ve moved the battery, the sensor can be easily broken.
- You should also test the alternator’s output, the IBS, the PCR, etc. to ensure they are functioning normally.
The stop/start unavailable warning also appears because of these parameters:
- Open door or hood.
- Unfastened seatbelt.
- Heated windshield.
- Climbing on a high slope.
- Active parking assistant.
- Overloaded ventilation.
- Faulty battery sensor.
- Faulty air mass sensor.
Read the owner’s manual or guide to learn more about your car’s stop/start system. The book should contain a ton of helpful information.
Auto repair shops cannot read all the codes on the system. Take your Jeep to the service department, at the very least. They can read your codes right there in the bay. Contrary to what many people believe, the system is actually quite intelligent.
- Jeep Commander Transmission Over Temp Problem: How to Fix?
- Stop Safely Vehicle Will Shut Off Soon: What to Do?
Every Jeep component must undergo self-checks. A code is generated if one is unsuccessful. Depending on what system failed, it will affect stop/start as a precautionary measure. Because of this, the engine won’t automatically shut off and restart.
To begin troubleshooting your problem, have your battery tested. Then check the electrical systems and, subsequently, the temperature of the engine and cabin. Also, check if all the parameters for the stop/start system to become available are okay.
Your Jeep won’t be harmed if stop/start is unavailable, but it is a sign of an issue that exists. Make a trip to a workshop right away if the error message frequently appears.