# Car's warning light flashing momentarily when car hits a bump or pothole (need answer fast) **URL:** \ **Category:** Factual Questions\ **Created:** [February 17, 2018, 1:28pm UTC](https://boards.straightdope.com/t/cars-warning-light-flashing-momentarily-when-car-hits-a-bump-or-pothole-need-answer-fast/808989 "2018-02-17T13:28:58Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![Velocity](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/velocity/32/18006_2.png) [@Velocity](https://boards.straightdope.com/u/Velocity)\ **Post date:** [February 17, 2018, 1:28pm UTC](https://boards.straightdope.com/t/cars-warning-light-flashing-momentarily-when-car-hits-a-bump-or-pothole-need-answer-fast/808989/1 "2018-02-17T13:28:58Z")
Anyone know the meaning of the car’s warning light flashing for a split-second (the triangular-shaped light thing) when a car hits a bump or pothole in the road, then instantly vanishing again? Seems like the implication is that, whatever component is damaged, is only damaged in that instant when the car sustains some forceful impact, then immediately reverts back to its undamaged state again? (2009 SmartCar, for whatever it’s worth.) ---
**Author:** ![jz78817](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jz78817/32/1028_2.png) [@jz78817](https://boards.straightdope.com/u/jz78817)\ **Post date:** [February 17, 2018, 1:38pm UTC](https://boards.straightdope.com/t/cars-warning-light-flashing-momentarily-when-car-hits-a-bump-or-pothole-need-answer-fast/808989/2 "2018-02-17T13:38:20Z")
> [@Velocity](#): > > Anyone know the meaning of the car’s warning light flashing for a split-second (the triangular-shaped light thing) when a car hits a bump or pothole in the road, then instantly vanishing again? > > Seems like the implication is that, whatever component is damaged, is only damaged in that instant when the car sustains some forceful impact, then immediately reverts back to its undamaged state again? > (2009 SmartCar, for whatever it’s worth.) according to [your owner’s manual](https://www.smartusa.com/resources/downloads/manuals/2009/owners_manual.pdf), that light indicates the electronic stability program (ESP) is activating. **Problem:** The ESP® warning lamp flashes while driving. **Possible causes/consequences and Solutions** : The ESP® has engaged because of detected traction loss in at least one tire. X When driving off, apply as little throttle as possible. X While driving, ease up on the accelerator pedal. X Adapt your speed and driving to the prevailing road and weather conditions. basically when going over a bumpy surface, the ESP is detecting something like an unplanned difference in wheel speeds or a certain movement of the car which makes it think it needs to activate. My Ranger will engage it’s stability control (AdvanceTrac in FordSpeak) and flash the light when I go over certain busted up roads- of which there are many in Michigan. So, normal behavior. nothing to be concerned about. and read your owner’s manual. ---
**Author:** ![Velocity](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/velocity/32/18006_2.png) [@Velocity](https://boards.straightdope.com/u/Velocity)\ **Post date:** [February 17, 2018, 1:40pm UTC](https://boards.straightdope.com/t/cars-warning-light-flashing-momentarily-when-car-hits-a-bump-or-pothole-need-answer-fast/808989/3 "2018-02-17T13:40:46Z")
> [@jz78817](#): > > according to [your owner’s manual](https://www.smartusa.com/resources/downloads/manuals/2009/owners_manual.pdf), that light indicates the electronic stability program (ESP) is activating. > > **Problem:** The ESP® warning lamp flashes while driving. > > **Possible causes/consequences and Solutions** : > > The ESP® has engaged because of detected traction loss in at least one tire. > X When driving off, apply as little throttle as possible. > X While driving, ease up on the accelerator pedal. > X Adapt your speed and driving to the prevailing road and > weather conditions. > > basically when going over a bumpy surface, the ESP is detecting something like an unplanned difference in wheel speeds or a certain movement of the car which makes it think it needs to activate. My Ranger will engage it’s stability control (AdvanceTrac in FordSpeak) and flash the light when I go over certain busted up roads- of which there are many in Michigan. > > So, normal behavior. nothing to be concerned about. > > and read your owner’s manual. Wonderful, thanks…I don’t know if I have ever cracked open that book…time to go get it. Wonder if this is typical of most other contemporary cars as well? ---
**Author:** ![jz78817](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jz78817/32/1028_2.png) [@jz78817](https://boards.straightdope.com/u/jz78817)\ **Post date:** [February 17, 2018, 2:44pm UTC](https://boards.straightdope.com/t/cars-warning-light-flashing-momentarily-when-car-hits-a-bump-or-pothole-need-answer-fast/808989/4 "2018-02-17T14:44:25Z")
> [@Velocity](#): > > Wonderful, thanks…I don’t know if I have ever cracked open that book…time to go get it. > Wonder if this is typical of most other contemporary cars as well? yes. the indicator light will be different depending on brand ( [this is what Ford uses](https://img.autobytel.com/car-reviews/autobytel/-ford-advancetrac-with-roll-stability-control-rsc/ford-stability-control.jpg) ) but any time the road conditions are sufficiently poor, you may see the stability control engage. the only time to be concerned is if that indicator stays lit steadily, that means a fault was detected in the stability control system and it is disabled. ---
**Author:** ![kayaker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kayaker/32/441_2.png) [@kayaker](https://boards.straightdope.com/u/kayaker)\ **Post date:** [February 17, 2018, 2:50pm UTC](https://boards.straightdope.com/t/cars-warning-light-flashing-momentarily-when-car-hits-a-bump-or-pothole-need-answer-fast/808989/5 "2018-02-17T14:50:20Z")
My Jeep Wrangler and my gf’s Subaru Crosstrek both do this. ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [February 17, 2018, 3:30pm UTC](https://boards.straightdope.com/t/cars-warning-light-flashing-momentarily-when-car-hits-a-bump-or-pothole-need-answer-fast/808989/6 "2018-02-17T15:30:38Z")
My Mazda has this, too, with the car and wavy tire tracks symbol, like the Ford above. ---
**Author:** ![Lucas\_Jackson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lucas_jackson/32/303_2.png) [@Lucas\_Jackson](https://boards.straightdope.com/u/Lucas_Jackson)\ **Post date:** [February 17, 2018, 3:41pm UTC](https://boards.straightdope.com/t/cars-warning-light-flashing-momentarily-when-car-hits-a-bump-or-pothole-need-answer-fast/808989/7 "2018-02-17T15:41:22Z")
> [@jz78817](#): > > So, normal behavior. nothing to be concerned about. > > and read your owner’s manual. And don’t drive over pot holes! 🙂 ---
**Author:** ![jz78817](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jz78817/32/1028_2.png) [@jz78817](https://boards.straightdope.com/u/jz78817)\ **Post date:** [February 17, 2018, 4:03pm UTC](https://boards.straightdope.com/t/cars-warning-light-flashing-momentarily-when-car-hits-a-bump-or-pothole-need-answer-fast/808989/8 "2018-02-17T16:03:16Z")
> [@Lucas\_Jackson](#): > > And don’t drive over pot holes! > 🙂 in Michigan right now that means “don’t plan on going anywhere.” ---
**Author:** ![RememberMe](https://avatars.discourse-cdn.com/v4/letter/r/5fc32e/32.png) [@RememberMe](https://boards.straightdope.com/u/RememberMe)\ **Post date:** [February 17, 2018, 9:49pm UTC](https://boards.straightdope.com/t/cars-warning-light-flashing-momentarily-when-car-hits-a-bump-or-pothole-need-answer-fast/808989/9 "2018-02-17T21:49:29Z")
> [@Velocity](#): > > Wonderful, thanks…I don’t know if I have ever cracked open that book…time to go get it. > Wonder if this is typical of most other contemporary cars as well? I would guess this issue is more prevalent for your car compared to other contemporary cars due to the small size, weight, and generally poor road handling characteristics. Sent from my iPhone using Tapatalk