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2019-2020 Hyundai Santa Fe auto start stop eliminator with 5.7-inch ISG memory harness. Skip repeated ISG OFF presses while retaining factory control.
Product function
Made for: The 2019–2020 Hyundai Santa Fe. The fitment table shows a 100% fitment match for each year. In these years the Santa Fe is a midsize SUV. No trim split is given, so check for the factory ISG (Idle Stop & Go) button and compare the connector photo.
In short: Out of the factory, ISG (Idle Stop & Go) switches back on at every start. The module keeps your previous selection, so one press is enough.
Order check: Check the year against the fitment rows and look for the ISG (Idle Stop & Go) button. Look at the connector in the photos before ordering. Aftermarket remote start, alarm or gateway devices on the same circuit need a check with support first.
Fitting: It connects at the ISG button circuit, between the switch and its factory plug. No software is changed.
Going back to stock: Unplug the module and reconnect the factory plug to return to the original behavior. Nothing has to be repaired afterwards because nothing was cut.
What it leaves alone: The original switch still does its job. It does not alter the engine tune, shift programming or charging. Factory rules for when the engine may stop still apply.
Ordering terms: Free shipping to the contiguous US, dispatched in 1–2 business days with about 3–4 days in transit. Returns within 45 days with pre-approval (20% restocking fee, buyer pays return postage). Covered by a 3-year limited warranty. Fitment questions go to support@automotivebypass.com (Mon–Fri, 9–5 PST); include the VIN.
Select your vehicle in the fitment guide to confirm this product is right for your year, make and model.
Description
This ISG memory harness is for the 2019–2020 Hyundai Santa Fe. It stores the last stop-start setting you chose, so if you turned ISG (Idle Stop & Go) off on one drive, it stays off the next time you start the engine. It connects at the ISG button circuit, between the switch and its factory plug.
Nothing is reprogrammed in the engine computer. The module only stands in for the button press you would otherwise make after every start, and it comes out without leaving a trace.
Vehicles and years covered
This part is listed for these vehicles, all marked 100% fitment match:
- Hyundai Santa Fe: 2019–2020
Trim levels are not split out in the table, so confirm that your vehicle has the stop-start button before ordering.
Why the button resets
On the Hyundai Santa Fe, ISG (Idle Stop & Go) shuts the engine down at a stop and fires it back up as the brake is released. You can switch it off with the dash button, but the choice is not saved. The next ignition cycle brings the default back. The module keeps the choice you made instead.
Battery notes for stop-start vehicles
If the stop-start indicator shows the system as unavailable, test the battery before anything else. On stop-start vehicles that is the most common cause. A replacement should match the original specification (AGM or EFB), and some manufacturers call for a battery monitor reset after the swap.
What the module does and does not do
- Carries your stop-start choice over to the next drive.
- Comes out in the same way it went in, with nothing cut.
- Does not disable warning lights or diagnostic functions.
- Fuel use changes only the way it would if you pressed the off button yourself.
Connecting it
It connects at the ISG button circuit, between the switch and its factory plug. Because it is plug-in only, removal is the reverse: unplug the module and reconnect the factory connectors directly. Keep the original clips and trim fasteners if you remove a panel to reach the connector.
Troubleshooting notes
A dead or weak battery, a charging problem or an unrelated module fault will change how ISG (Idle Stop & Go) behaves with or without this part installed. Scan the vehicle for stored codes, test the battery and confirm the system works normally with the factory button before installation. That baseline makes any later issue easy to pin down.
Day-to-day use
Some owners only want stop-start off in certain seasons or on certain trips, such as towing a trailer or crawling through summer traffic with the A/C working hard. Because the module remembers whatever you chose last, it works both ways: leave the system off for a week, then switch it back on with the factory button and it stays on.
Things that already block an auto stop
Auto stop needs several conditions at once: a warm engine, enough battery charge, moderate cabin heating or cooling demand, and the vehicle fully stopped with the brake held. If any is missing, the engine keeps running. The module only remembers the button state; the factory controller still decides whether a stop is allowed.
Fitment check
- Model year and model match a row in the table above (2019–2020 Hyundai Santa Fe).
- Your Hyundai Santa Fe has the factory stop-start button. Base trims or engines without stop-start have nothing for the module to remember.
- The connector at your install point matches the one in the product photos.
- The battery and charging system test good and no warning lights are on.
- No aftermarket remote start, alarm or gateway bypass is wired into the same circuit. If one is, email support before ordering.
- If you are unsure, send your VIN to support@automotivebypass.com and we will confirm fitment.
Shipping, returns and warranty
Free standard shipping covers the contiguous US, with dispatch in 1–2 business days and 3–4 days on the road after that. You have 45 days to request a return (pre-approval required, 20% restocking fee, buyer-paid return shipping). The module is backed by a 3-year limited warranty. For order or fitment questions, write to support@automotivebypass.com between 9 and 5 Pacific, Monday through Friday.
Questions & Answers
Will ISG (Idle Stop & Go) come back on when I restart my Hyundai Santa Fe?
Not if you turned it off before shutting down. The module repeats your last selection at the next start. If you leave it on, it stays on.
Which Hyundai Santa Fe years does this fit?
The listed range is 2019–2020. Check the fitment table on this page against your exact model year.
Why does my Hyundai Santa Fe sometimes not auto-stop even when the system is on?
The factory logic checks battery charge, engine temperature, climate load and other inputs. If any are outside range it keeps the engine running. The module does not affect those checks.
Does the stop-start button still work after installation on the Hyundai Santa Fe?
Yes. The factory button works normally. The module simply stores whatever you chose last.
Does it change engine power or fuel trims?
No. It does not reprogram the engine or transmission computers. It only stores the stop-start button state.
Will it fix a "stop-start unavailable" message?
No. That message usually points to the battery or a sensor. Diagnose and repair that first.
What happens if I unplug it?
The vehicle returns to the factory default, with ISG (Idle Stop & Go) switched on at every start.
Does it change how the battery is charged?
No. Charging is still managed by the vehicle. Stop-start vehicles normally use an AGM or EFB battery built for frequent restarts; replace it with the same type when it wears out.
Why does ISG (Idle Stop & Go) turn itself back on every time?
Automakers set stop-start to default to on at each start. Under EPA test rules, a system that stays off after shutdown is tested both on and off and the results are averaged, which lowers the rated fuel economy, so most systems reset at every key cycle. The module carries your last choice across that reset.
Can I remove it later?
Yes. Unplug the module and reconnect the factory connector; the vehicle returns to its stock default.
How does it connect?
It connects at the ISG button circuit, between the switch and its factory plug.
Does my Hyundai Santa Fe need the factory stop-start button for this to work?
Yes. The module works with the factory stop-start system and its button. A vehicle built without stop-start has no setting for it to remember.
Is this the same part for every Hyundai?
No. Connectors and the module that holds the stop-start state differ by platform, so this SKU is matched to the fitment rows on this page. Send the VIN to support if you are unsure.
Vehicle Fitment
Additional Information
- Brand
- Automotivebypass
- Fits vehicle make
- Hyundai
- Product type
- Auto Start Stop Eliminator
- SKU
- RC-ASSE-45-01
- Brand
- Hyundai
- Installation
- Confirm the connector location and installation steps for your exact vehicle before ordering.
- Package
- Review the product description and included contents before ordering.
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