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I mean it is normal for the hood open message to flash on for a second or two when the vehicle is started with the SmartStopStart module installed. Then it will automatically go off and stay off during the drive.
 

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This is in reference to inserting a painted resistor into the 5 amp fuse receptacle on top of the battery. I came up with the idea of using a 100 ohm resistor because I had one available and Ohm's law suggested it would be about right. This continued to work without problems for over a year. Research has revealed that the lead is the sensor for the "Intelligent Battery System" and the resistor raises the system voltage from 13.9 to 14.9 volts. This is at the high end of the recommended charge voltage for an AGM battery like the Cad's. Experimenting with a precision variable resistor demonstrated the desired defeat of stop-start at 82 ohms which results in a system voltage of 14.7 volts. This may or may not be bad for the battery but it has a 4 year, 50,000 mile guarantee. Also it's duty cycle is reduced by about 90% by eliminating stop-start. After warranty, in the event of battery failure, I'll install a traditional lead acid battery as I've had mixed experiences with AGMs on boats. I have an idea for a more sophisticated approach to eliminating stop-start but the modification of the wiring would be obvious and I would like to avoid questions from the dealer if something goes wrong. The 82 ohm fuse is working fine for me although it is necessary to drive with it for a day before stop-start becomes inoperative. If you want to avoid soldering, you must use an adapter like an Add-a-circuit fuse TAP and bend the resistor leads into U shapes. The GM receptacle is just slotted steel and will not hold the fuse wires https://www.amazon.com/dp/B01LFXA5YQ/ref=sspa_dk_detail_0?psc=1&pd_rd_i=B01LFXA5YQ&pf_rd_m=ATVPDKIKX0DER&pf_rd_p=21517efd-b385-405b-a405-9a37af61b5b4&pd_rd_wg=2tAKx&pf_rd_r=ZJACWTWRH1E75YRPF4VT&pf_rd_s=desktop-dp-sims&pf_rd_t=40701&pd_rd_w=FsLPW&pf_rd_i=desktop-dp-sims&pd_rd_r=976484be-f8bb-11e8-9397-9daa0eb60073. The fuses are available at Frys, 997676, https://www.frys.com/product/997676?site=sr:SEARCH:MAIN_RSLT_PG Second photo below shows installed resistor in Add-a-circuit in fuse holder cancelling stop-start. You could cut off unneeded wire and shave off top slots to get plastic battery cover to close.
 

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2017 XT5, Platinum, Dark Granite Metallic, 20" Ultra-Bright
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Therein lies the danger in tinkering with sophisticated electrical systems such as that in the XT5 without full knowledge of possible side effects. "This may or may not be bad for the battery but it has a 4 year, 50,000 mile guarantee." The box that emulates an open hood for a few moments at the beginning of a drive cycle is a far safer modification.

Thank you Arminius for alerting the followers of this thread that there are probably long term issues. Early demise of a very expensive battery is not desirable, say nothing about causing the electrical system to operate at voltage levels higher than design parameters. There may be additional undesirable voltage related damage long term.
 

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Stop-start poses an imminent danger while battery failure under warranty is remote, conjectural and devoid of substantial injury. After enabling stop-start for my resistor experiment, I practically rear-ended a car. The engine starts upon lifting one's foot from the brake and my foot moved quickly to the accelerator as the engine started on a cold morning: the car lurched forward! Is this another example of rich idealists imposing an immediate penalty upon those of us would prefer to face global warming when and if it arrives? Another carbon tax?
 

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Of course the battery warranty will be void if the electrical system voltages have been tinkered with.
 

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My plan is to open the hood if the car refuses to start and substitute the original fuse for the modified fuse/resistor. This is a thumb and forefinger operation. The dealer reports no faults and my personal OBD2 reader says all is well. I would not want to tell the dealer of the overvoltage for fear he might not honor the warranty. I think this is a better plan than to drive in with an apparent science project under the hood. You'd get a rep at the dealer you know.
 

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A motivated hobbyist could figure out how to short out the resistor (use 100 ohm) when the car is moving. The system voltage would then be standard except when the car was stationary and stop-start needed to be defeated. I tried a solid state sail switch in the plenum above the radiator but it did not react quickly enough. A mechanical sail switch alongside and behind the front plate might do it. A 12 volt motion sensing light switch from a trailer/RV store mounted in the engine compartment and facing the road below might work. But then I would be driving a science project! I'll just stick with the 82 ohm quick change fuse/resistor till I get really bored!
 

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My plan is to open the hood if the car refuses to start and substitute the original fuse for the modified fuse/resistor. This is a thumb and forefinger operation. The dealer reports no faults and my personal OBD2 reader says all is well. I would not want to tell the dealer of the overvoltage for fear he might not honor the warranty. I think this is a better plan than to drive in with an apparent science project.
And hope to accept without conscience a replacement for the battery you knowingly caused an early demise.
 

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GM deserves all the excrement we can throw at it for foisting this car spoiler (stop-start) upon us. I sat in a new model XT4 during my last oil change and the sales manger assured me that start-stop can be permanently turned off in it. I'm guessing GM could turn off our XT5 stop-start with a model wide software download. I'd like to see a wave of lawsuits against GM claiming low speed rear enders and pedestrian crushing incidents. I'm not worried about the remote possibility of failing to tell GM that a failed battery had been operated at .8 volts overvoltage and that that might have contributed to its premature demise. More likely is an unexpected and hazardous battery or starter failure in an unmodified XT5 on a freeway in rush hour stop and go as stop-start taxes the starting system past its limits. Most stop-start systems have two batteries to avoid this real possibility. New starters look like old starters with brushes that wear out and starters cost $325.00 or so.
 

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A soldered stop-start eliminator may be made by buying a pack of Micro-2 fuses. Burn one out by shorting it across the battery using alligator clips so as not to leave an arc mark on a prong (or file it smooth.) Place the fuse in your shop vice with the ridge side up and one hole (on each leg) exposed above the tightened jaws. Wearing gloves, heat an old kitchen knife in a propane torch and remove the exposed plastic with your hot scalpel. Bend the leads of the 82 ohm resister in to the width of the holes and then at right angles. Trim them down to about a quarter inch or less and put the leads through the exposed holes of the fuse. Crimp the wires on the legs. Remove the fuse from the vise and solder the resistor in with a low wattage soldering iron. Check the resistance for 82 ohms. Paint the assembly (except for the legs) black with liquid electrical tape for camouflage. When it is dry, substitute it for the yellow 5 amp fuse on top of the positive battery terminal but don't quite bottom it out. By design or on account of the modification, a fully seated fuse can short and enable stop-start by accident. An unpainted 100 ohm assembly is displayed.
 

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why would anyone use SmartStopStart, ( which creates issues with remote start ) when you can get this " Range AFM Disabler " which not only stops the dreaded start stop but also keeps the xt5 in 6 cylinder mode for full power all the time. And had no remote start issues. Would rely like input from some one who has either. I am leaning toward the fuse and 82 ohm resistor but would like input about the products listed. Range AFM seam like the cats meow just plug in or unplug to issues.https://rangetechnology.com/afm-disabler/
 

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Thank you for identifying AFM disabler. Sounds great although I have not noticed cylinder deactivation as a problem. I've got a new idea to defeat stop-start which I will publish in a new thread. However, it requires wiring and I like the simplicity of the AFM disabler.
 

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Thank you for identifying AFM disabler. Sounds great although I have not noticed cylinder deactivation as a problem. I've got a new idea to defeat stop-start which I will publish in a new thread. However, it requires wiring and I like the simplicity of the AFM disabler.
may Not necessarily be a problem but a added bones is it deactivates the start stop at the same time
 

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So... has anyone taken the plunge on this thing yet? I'm super interested in it, it does seem like "the cat's meow" but obviously I'm wary of screwing anything up electrical-wise in a vehicle with the amount of tech we're dealing with here. I'd love to know if anyone is using one and what they think.

Start stop doesn't usually bother me but I sure wish I had the option to turn it off.

I'm currently training myself to do the trick where you flick down to M and back to D when waiting at a stop light to keep it running. So far so good.
 

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I see some people here like to push and advertise some commercial type systems or just feel better by getting confirmation of other people doing the same.

But adding the 82 ohm or 100 ohm resistor does not make any change in the power management system, only if you don't remove the resistor or switch back and forth between resistor to fuse.

The vehicle algorithm continuously estimates battery state-of-charge based on adjusted net amp hours, battery capacity and initial state-of-charge.

So , we are lucky that the calculation is based on present state and initial state, so if the resistor is not removed, it is all fine for the electrical power management system, and the system can go in to different charging modes--But only if permitted by many other conditions.

For example: it will not go in to Fuel Economy Mode if the Headlamps are on or the AC is on.

Or, any Voltage Reduction Mode will not take place when ambient air temperature is under 32°F
 

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Hi Guys,

I came across this thread when searching Net for safe deactivating stop/start fix, I don`t own a Cadillac but own a couple of Mercs, a 2012C Class Coupe CGI blueefficiency petrol and a 2015 SLK 200 CGI petrol.

I have been running both cars for over 6 months with a deactivated stop/start, the method being used is to disconnect the battery sensor connected to the negative post of the. This stops the EMU from reading the SOC of the battery and hence it won`t activate stop/start and leaves the stop/start symbol on dash in yellow (off), on the SLK the symbol goes out (off). With the sensor disconnected the EMU also changes the alternator charging regime to standard continuous charging between 13.8 to 14.3 volts, in this regime the alternator always tries to keep the battery fully charged whereby in smart mode the EMU instructs the alternator to charge as little as possible to save fuel and keep the SOC as close to 75% charge as possible, this also leaves room for any regeneration at high charge around 15-16 volts, 75% SOC leaves little room for emergencies, thats why drivers are having battery problems. As the ECU does not now know the SOC and there is no stop/start or regeneration any lead acid battery can be used as long as it is housed under the hood and not in the car, if it is in the car it needs to be spill proof, Gel.

Both cars have recently passed the UK MOT with no issues, the SLK also had a tuning box fitted.

What I ask is, does your resistor hack leave the charging regime in smart with regen or does it like my hack put charging into standard continuous.

Regards Robuk.
 

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Sorry can`t find edit, meant to say,

The method being used is to disconnect the battery sensor connected to the negative post of the main starter battery under the hood.
 

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I had proposed a couple resistor hacks for the XT5 in which a resistor is substituted for the 5 amp fuse on the POSITIVE battery terminal for the Intelligent Battery System sensor circuit. The GM system has 6 different charging modes and I can't tell you which mode was the result although both resistors cancelled stop-start. Both also resulted in mildly increased system voltages. 100 ohms was chosen arbitrarily. The resistance was experimentally reduced to 83 ohms in an effort to defeat stop-start with minimal voltage increase. While no adverse effects were noted with either hack, I came up with another system which only fools the battery voltage sensor when the car is not running. This seems strange but the GM system also checks battery health after shutdown, after a period of inactivity. With a questionable battery, stop-start is not authorized for the next cycle (at least that's my theory). I've been very happy with the system as described here: https://www.cadillacforums.com/forums/cadillac-xt5-first-generation-forum-2017/1076328-start-stop-defeat-idea-new-free.html
 

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I thought I would post this as a follow up since I've had the start/stop module installed for months now with no issues. I just had an oil change service completed. I didn't disconnect or remove the start/stop module prior to going to the dealer. There was absolutely no issue. I didn't mention that it was installed and the dealer had no idea that it was installed. The oil change service was performed with no problems. I can understand that some owners might want to remove it prior to having the vehicle serviced, but based upon my experience I'm leaving it connected.
 

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I've had the SmartStopStart module installed for about 6 months now in our 2018 XT5. It does work, but it has had some issues / side effects.

1) If you jump in the car and start it right away, the module won't function. The maker says there's a required 3 second delay from the time you open the door. At times, when in a hurry, it's easy to beat this 3 second timer.

Now, the maker said the 3 second delay was needed to allow the Remote Start function, which leads me to...

2) The remote start function has never worked since installing the module. Every time we try, the car throws a code and the check engine light comes on. This last time we tried remote start, the alarm (annoyingly) went off.

It's becoming summer here in Texas, so I'll probably remove the module. The A/C tends to limit the car's natural ability to stop the engine. We also need remote start to work again so we can cool the car off before getting in. I'll probably start looking for a new solution, or read back in this forum for other ideas. Just sharing my personal results with one of the options in the market.
 
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