How to Reset Jeep Auto Start/Stop (ESS) — and Get It Working Again

Jeep’s Auto Start/Stop (often called ESS) is one of those features you don’t notice until it won’t behave. Maybe it says “Not Ready”. Maybe it stopped shutting the engine off at lights. Or maybe you changed a
battery and now the system feels “off.”

Here’s the simple truth: most “reset” requests are really one of three things:

• Turning ESS back on after it was turned off for the drive
• Clearing the “Not Ready” state (usually battery, temperature, or cabin comfort checks)
• Fixing ESS after service (battery swap, sensor issue, or stored faults)

Below, you’ll get the quick reset steps first (the ones that solve most cases), then you’ll see pro-grade scan tools that make this fast and clear if the basic steps don’t fix it.

Quick Picks (Top Tools to Diagnose/Reset Jeep ESS)

If your Jeep shows “Service Start/Stop System,” or ESS stays unavailable for days, a real diagnostic tool is usually the shortest route to answers.

• Best Overall:
  Autel MaxiSYS MS919

  Full-system scans, live data, active tests, and the “why” behind ESS “Not Ready.”

• Best Budget (Still Pro-Level):
  LAUNCH X431 PRO5

  Strong diagnostics and bidirectional testing without Ultra-tier pricing.

• Best Premium:
  Autel MaxiSYS Ultra S2

  Top-end tablet for tough, recurring electrical/ESS issues and deeper testing workflows.

How to Reset Jeep Auto Start/Stop (Step-by-Step)

Step 1: Make sure it’s not just “turned off for this drive”

On many Jeep models, the ESS button only disables Auto Start/Stop until the next key cycle. So the quickest “reset” is simply:

• Park safely
• Turn the Jeep fully off
• Open the driver’s door and wait about 30 seconds
• Restart and see if ESS behavior returns

If ESS still shows “Not Ready,” that’s often not a failure. It’s the system protecting you from a weak restart situation or keeping cabin comfort stable.

Step 2: Check the easy “Not Ready” triggers

ESS checks several safety and comfort conditions before it will shut the engine down. If any of these are “off,” the system can refuse to activate:

• Driver seat belt not buckled
• Driver door not fully closed
• Steering angle or vehicle conditions not stable (varies by model)
• Cabin heating/cooling demand is high (max A/C, max defrost, etc.)
• Battery temperature too hot or too cold
• Battery charge is low

Quick test: buckle up, close the door firmly, turn off high-load cabin settings for a few minutes, then drive normally and check again at a safe stop.

Step 3: Do a battery “recovery reset” (most common fix)

If your main battery (or the auxiliary battery on some Jeep models) is weak, ESS will often disable itself. That’s normal. The system wants enough reserve power to restart the engine smoothly every time.

• Drive 20–40 minutes to let the charging system recover
• During that drive, avoid heavy electrical loads if possible (heated seats, max defrost, etc.)
• Try again after the engine is warm

If this brings ESS back, the “reset” was simply restoring the battery state. If it keeps dropping out again, battery health (or a charging issue) becomes the main suspect.

Step 4: If you recently replaced a battery, expect ESS to be picky for a while

After a battery change, ESS can take some driving time to settle, especially on vehicles that track battery status closely. If your Jeep has both a main and auxiliary battery, a weakness in either one can keep ESS unavailable.

If you see a warning like “Service Start/Stop System”, or ESS stays unavailable for several days of normal driving, it’s time to check for stored fault codes and battery/charging data instead of guessing.

Step 5: Use a scan tool “reset” (the clean, reliable method)

A professional scan tool helps because it can do more than just read engine codes. With the right tool, you can:

• Read ESS-related codes across multiple modules (not only the engine computer)
• Check live battery/charging data and see whether voltage and current are healthy
• Confirm which condition is blocking Auto Stop (battery charge, temperature, HVAC demand, etc.)
• Clear faults after repairs and verify the problem is actually gone

Tip: many newer FCA vehicles use a security gateway that restricts deeper access. If your Jeep is newer, choose a scanner that supports the needed gateway access method for FCA vehicles.

Step 6: A hard reset (use with caution)

Some owners try a “hard reset” by disconnecting the battery for a short period. This can reset modules and clear temporary states, but it can also trigger radio/security resets or other side effects. If you choose to do it:

• Follow your owner’s manual and safety steps
• Make sure you have any radio/security info you might need
• Disconnect the negative terminal first, reconnect it last

If you’re not comfortable doing this, skip it. A scan tool is safer and more informative because it tells you what’s wrong rather than hoping a power cycle fixes it.

Buyer’s Guide: Choosing the Right Tool for Jeep ESS Issues

If you only want to turn ESS off for one drive, you don’t need a tool. But if you want to restore ESS function, fix warnings, or find out why it’s blocked, these features matter:

• Full-system diagnostics: ESS problems can live in BCM, powertrain, battery management, or body modules.
• Live data: Battery voltage, charging current, temperatures, and status flags can explain “Not Ready.”
• Bidirectional controls: Lets you run active tests and confirm switch/sensor behavior.
• Battery/charging focus: ESS depends heavily on battery health and charging performance.
• FCA gateway support: Many newer Jeeps require proper access for deeper diagnostics.
• Updates and support: Coverage changes by model year; updated software can be the difference.

Detailed Product Reviews (Pro Tools Often Priced $2,000+)

Autel MaxiSYS Ultra

Who it’s for: Jeep owners who want shop-level diagnostics for stubborn ESS faults and broader electrical issues.

Key Benefits:

• Deep, full-system diagnostics across modules
• Strong live data and guided fault-finding flow
• Great when ESS is blocked by battery/charging or module faults

Pros:

• Fast hardware and a big screen for long diagnostic sessions
• Excellent for tracking “Not Ready” causes without guesswork
• Useful far beyond ESS (sensors, network issues, drivetrain, body, etc.)

Cons:

• Big buy if you only need it once
• Update/subscription terms depend on the package and seller

Final Verdict: If your Jeep keeps disabling ESS and you want real answers fast, this level of tool gets you there.
See it on Amazon.

Autel MaxiSYS Ultra S2

Who it’s for: People who want a newer, high-end Autel platform for recurring electrical problems and deeper testing.

Key Benefits:

• Premium diagnostic platform with modern workflow tools
• Great for intermittent issues that come and go
• Excellent for owners who keep vehicles long-term and do their own troubleshooting

Pros:

• Strong for tracing tricky ESS faults that don’t show up every time
• Built to handle complex module and electrical situations
• High-end experience from start to finish

Cons:

• Premium pricing
• More tool than most casual owners truly need

Final Verdict: If you want a no-compromise scanner for ESS and everything around it, this is the premium pick.
Check current price.

Autel MaxiSYS MS919

Who it’s for: Jeep owners who want deep diagnostics without stepping up to the Ultra tier.

Key Benefits:

• Full-system diagnostics and strong live data support
• Great balance of capability and long-term value
• Ideal for chasing the real cause behind ESS “Not Ready”

Pros:

• Excellent for reading codes across the Jeep’s systems
• Strong for battery/charging checks that affect ESS
• Solid choice if you maintain more than one vehicle

Cons:

• Still priced in the pro category
• Update terms depend on package and seller

Final Verdict: For many Jeep owners, this is the sweet spot: deep enough to solve ESS issues, without Ultra-level cost.
View it on Amazon.

Autel MaxiSYS MS909

Who it’s for: Serious DIY owners who want reliable full-system diagnostics for repeated troubleshooting.

Key Benefits:

• Strong full-system scanning and practical troubleshooting tools
• Great for diagnosing charging and battery states that impact ESS
• Useful across many makes and models

Pros:

• Finds causes, not just symptoms
• Strong for recurring warning messages
• Good long-term tool if you keep your Jeep for years

Cons:

• Overkill if you only want a quick one-time check
• Feature coverage can vary by kit

Final Verdict: If ESS issues keep returning, this helps you stop guessing and start verifying.
See it on Amazon.

LAUNCH X431 PAD VII

Who it’s for: Owners who want broad coverage, strong service functions, and bidirectional testing for modern vehicles.

Key Benefits:

• Full-system diagnostics with strong testing features
• Built for chasing issues that block features like ESS
• Great for owners who work on multiple vehicles

Pros:

• Solid capability in the pro category
• Good when electrical issues cross over multiple modules
• Comfortable for longer use sessions

Cons:

• Gateway access needs may vary by model year
• Buy from a reputable seller for support and updates

Final Verdict: A strong pro platform when you want real testing power for ESS, sensors, and modules.
Check it on Amazon.

TOPDON Phoenix Smart

Who it’s for: Owners who want a modern diagnostics tablet that’s strong on electrical troubleshooting.

Key Benefits:

• Strong diagnostics for many makes and years
• Helpful for battery/charging and sensor-driven ESS problems
• Good mix of speed, screen size, and everyday usability

Pros:

• Comfortable screen for reading live data clearly
• Good for recurring problems that need tracking over time
• Useful beyond ESS (electrical, body, drivetrain, etc.)

Cons:

• Feature sets can vary by package and region
• Confirm compatibility with your Jeep’s model year and access needs

Final Verdict: If your ESS problem is part of a bigger electrical story, this tool helps you see the full picture.
See current price.

Comparison Table

Name	Key Features	Specs/Capacity	Price Link
Autel MaxiSYS Ultra	Deep full-system diagnostics, advanced workflows	Pro tablet + VCI kit (varies by package)	Check price
Autel MaxiSYS Ultra S2	Premium diagnostics for recurring issues	High-end tablet hardware (varies by package)	Check price
Autel MaxiSYS MS919	Full-system scan, live data, active tests	Pro tablet + VCI kit (varies by package)	Check price
Autel MaxiSYS MS909	Full-system diagnostics, strong troubleshooting	Pro tablet + VCI kit (varies by package)	Check price
LAUNCH X431 PAD VII	Bidirectional testing, service functions	Pro tablet platform (varies by package)	Check price
TOPDON Phoenix Smart	Modern diagnostics, strong electrical focus	10.1″ class tablet (varies by package)	Check price

FAQ

Why does my Jeep say “Stop/Start Not Ready”?

Most of the time it’s battery charge, battery temperature, or a comfort/safety condition like the seat belt, door, or cabin heating/cooling demand. ESS is picky because it must restart the engine every time without drama.

Is there a real “reset button” for Jeep ESS?

Not usually. Many Jeeps let you disable ESS for that drive, but it returns on the next restart. A real reset is clearing what’s blocking the system (battery recovery, stored faults, or a sensor/charging issue).

Will a weak battery really disable Auto Start/Stop?

Yes. ESS depends on strong battery reserve. If the vehicle thinks the restart could be rough or unreliable, it will keep the engine running instead.

Do I need a scan tool to get ESS working again?

Not always. If the issue is simply low battery charge, a longer drive may bring ESS back. But if you have warning messages, stored faults, or recurring issues, a pro scan tool saves time and avoids random part swapping.

How do I stop guessing and diagnose it quickly?

Pull full-system codes and check live battery/charging data. The right scanner can also show which condition is blocking Auto Stop, so you know what to fix first.

Conclusion: “Reset” ESS by Removing What’s Blocking It

When Jeep Auto Start/Stop won’t work, it’s rarely random. Most of the time, it comes down to battery charge, battery temperature, or a basic safety/comfort setting. Handle the simple checks first, and you may get ESS back the same day.

But if ESS keeps going unavailable, or you’re seeing “Service Start/Stop System,” stop guessing. A real diagnostic tablet tells you what the Jeep is unhappy about, so you can fix the cause instead of chasing symptoms.

If you want one tool that can handle ESS problems today and real repairs later, start here:
Check the Autel MaxiSYS MS919 on Amazon.