Stop/Start Unavailable Service Stop/Start System: Causes and Fixes

Jeep auto start/stop not working error is a critical issue because that system is an ingenious fuel-saving feature that automatically shuts off your engine when you brake to a stop and restarts it when you lift your foot off the brake. This technology helps conserve gas and reduce emissions – a win-win for you and the environment!

There are a variety of potential causes for a Jeep auto start/stop not working issue and that system to stop functioning properly, including weak batteries, damaged wiring, malfunctioning starter motors, failed alternators and faulty sensors that the system relies on. Software glitches, parasitic draws, extreme weather conditions and accidental misuse can also result in the fuel-saving auto start/stop feature becoming disabled. Thorough troubleshooting and replacement of any damaged components are key to restoring normal operation of the system.

If your are Jeep owner you will face this issue at any point while you own your vehicle. And this issues is common among other vehicle brands and models too.

The goal of this post is to provide Jeep owners with solutions for diagnosing and troubleshooting common issues that cause the auto start/stop system to fail. I’ll walk through the main problems that could knock this feature offline and show you how to pinpoint and fix the issue so you can get back those fuel-saving auto engine shut-offs.

Whether it’s a faulty sensor, software glitch, or electrical gremlin that has your system on the fritz, you’ll find tips here to get your Jeep’s auto start-stop working like new again. Let’s dive in!

How the Auto Start/Stop System Works

Before we get into troubleshooting, let’s do a quick rundown of how Jeep’s auto start/stop system works its magic:

• It automatically shuts off the engine when you brake to a complete stop, like at a red light or stop sign. This eliminates fuel usage while idling.
• Once you lift your foot off the brake pedal, sensors detect this and quickly restart the engine so you can accelerate and drive away.
• The system relies on a network of sensors to monitor conditions like battery charge, engine temperature, whether the hood is open, and more.
• These sensors communicate with the vehicle’s computer to seamlessly stop and restart the engine when conditions permit.
• If the sensors detect any issues like low battery voltage or engine temp not reached, they’ll prevent the auto shut off and restart.

So in a nutshell, the system uses sensors to know when to automatically turn the engine off to save fuel and when to restart it again for driving. Now let’s look at why this handy feature can fail.

Why Your Jeep Auto Start Stop Not Working? Step-by- Step Fixes

When your Jeep’s auto start/stop system stops functioning properly, there are a few common culprits to blame. Let’s look at some of the top reasons the system can fail:

Weak or Faulty Battery

The auto start/stop feature needs adequate battery voltage to operate the various sensors and restart the engine. A weak battery, loose cable connections or corroded terminals can prevent the system from working properly.

Solutions: Test your battery voltage and the integrity of all connections. Clean any corrosion from battery terminals. If your battery is old or damaged, replacement is the fix.

Malfunctioning Starter Motor

The starter motor is responsible for firing the engine back up when you take your foot off the brake. If this component is damaged or worn out, the system won’t be able to automatically restart the engine.

Solutions: Inspect the starter motor wiring for any corrosion or damage. Replace the starter motor if it is determined to be faulty.

Alternator Failure

While driving, your Jeep’s alternator charges the battery. If the alternator belt is loose or slipping, or the alternator itself is failing, the battery may not get adequately recharged for the system to operate.

Solutions: Check the condition of all alternator belts and replace if worn. If the alternator is not properly charging the battery, it will need to be repaired or replaced.

Damaged Sensor(s)

The auto start/stop relies on input from sensors that monitor everything from engine temperature to whether the driver’s door is open. If any relevant sensor is damaged or malfunctioning, it cannot provide the proper signals to the system.

Solutions: Troubleshoot all sensors related to the auto start/stop system and replace any faulty ones. Also check for and clear any debris that could be obstructing sensors.

Software Glitches

Like any advanced automotive technology nowadays, the auto start/stop system can be susceptible to software bugs and errors. These may require professional diagnosis and repair.

Solutions: A dealership technician can troubleshoot the system for any underlying software issues and potentially provide ECU updates or reflash if needed.

Environmental Factors

Extreme high or low temperatures can also cause temporary malfunction of the auto start/stop system. When it’s very hot or cold, the demands on the battery and recharging system can be enough to disrupt operation.

Solutions: Closely monitor battery charge in temperature extremes. Perform preventative battery and charging system maintenance before winter.

Short Trips and Parasitic Draws

Frequent short trips that don’t allow the battery to fully recharge coupled with electrical parasitic draws can cause the battery to become depleted over time. This may prevent the auto start/stop from functioning.

Solutions: Take longer drives periodically to allow the charging system to fully top off the battery. Check for any constant electrical draws when the Jeep is off. Monitor battery voltage regularly for declines.

Other Causes

• The system will not shut off the engine if the hood or doors are detected as open. Check for any latch issues.
• Low engine temperature can prevent auto shut off until fully warmed up. Allow proper warm-up time.
• Transmission issues may disrupt signaling between gear selector and brake pedal position switch.
• Inadequate oil pressure detected can block auto shut off to protect engine. Check oil level and quality.
• The system has to meet pre-programmed criteria regarding velocity, acceleration and climate control settings before allowing automated start. Faulty input signals or software flaws could interfere with determining if criteria are met.

How to Reset the Auto Start/Stop System

If you’ve addressed any underlying issues causing your auto start/stop malfunction but the system still isn’t working right, try resetting it:

• Turn the ignition to the “On” position but do not start the engine
• Locate the auto start/stop disable button and press it for at least 10 seconds until the light blinks
• Turn the ignition back to the “Off” position and wait 15 seconds
• Restart the vehicle and the auto start/stop system should now be reset!

Resetting can often clear any erroneous fault codes or glitches to give the components a fresh start.

You can also try resetting by briefly disconnecting the battery or intelligent battery sensor. Just be sure to reattach and reboot the system afterwards.

The reset process allows all sensors and the ECU to recalibrate and hopefully get your auto start-stop feature back up and running.

Common Auto Start/Stop Mistakes to Avoid

To keep your Jeep’s auto start/stop performing optimally, beware of these common snafus:

• Accidentally pressing the system disable button. This will turn the feature off until it’s re-enabled.
• Ignoring warning lights related to the auto start/stop system. Don’t overlook indicators of an underlying problem.
• Installing aftermarket products like radios that can interfere with system sensors. Ensure all add-ons are compatible.
• Neglecting faulty sensors. Promptly replace any damaged sensors that are integral to the auto start/stop feature.

Staying aware of these potential pitfalls will allow you to maximize the benefits of your Jeep’s auto start/stop technology. Quickly addressing any issues that arise can help keep the system running smoothly for miles to come.

Let’s Review Key Auto Start/Stop Takeaways

Hopefully this overview gave you a better understanding of what can cause your Jeep auto start stop not working issue and how to get it functioning properly again.

The key takeaways are:

• Auto start/stop relies on battery voltage and sensors to seamlessly shut off and restart the engine.
• Faulty batteries, starters, alternators and sensors are common culprits when issues arise.
• Test components thoroughly and replace damaged parts promptly.
• Reset the system after repairs to clear any glitches.
• Avoid accidental misuse and be proactive with maintenance.

Don’t resign yourself to forever missing out on the gas savings and emissions reductions from this system! With diligent troubleshooting and component replacements as needed, you can get your Jeep’s auto start/stop working like new again.

I encourage you to thoroughly diagnose any underlying issues rather than ignoring a malfunctioning system. And perform preventative checks and battery care to maximize its performance. With some awareness and proactive care, your auto start/stop can go the distance.