Issue with Waze app
04-13-2020, 08:06 PM
#1
Drifting
Thread Starter
Issue with Waze app
Does anyone else have an issue with Waze reading the speed way lower than actual in their Vette and only in their Vette? Through Carplay or on the phone itself the speed in Waze is way low. Its normal in other vehicles though, it's only the Vette. It is the strangest thing.
04-13-2020, 08:43 PM
#2
Melting Slicks
Does anyone else have an issue with Waze reading the speed way lower than actual in their Vette and only in their Vette? Through Carplay or on the phone itself the speed in Waze is way low. Its normal in other vehicles though, it's only the Vette. It is the strangest thing.
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Vegas1500 (04-13-2020)
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Bavaria (04-14-2020)
04-13-2020, 10:24 PM
#5
Waze has always matched my speedo, in all vehicles, including 2 vettes
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rico750sxi (04-13-2020)
04-13-2020, 10:33 PM
#7
Drifting
Thread Starter
04-13-2020, 10:52 PM
#9
04-14-2020, 07:40 AM
#10
Drifting
Thread Starter
04-14-2020, 07:41 AM
#11
Drifting
Thread Starter
04-14-2020, 08:12 AM
#12
GPS speed as displayed in Waze will ALWAYS be lower than what the car is indicating. Speedo's always overread, some more than others. This is a known fact.
https://www.theglobeandmail.com/glob...ticle11487709/
Look at the above chart based on a Scion’s technical guide. At low speeds you’re potentially going faster than the speedometer says, but at 100 mph you’re going at least three miles per hour slower.
Compare this chart to the first one. The most a speedometer can be off at that same 100 mph (160 kph) is nearly 13 mph. This is why many BMW and Porsche drivers notice their speedometer is off.
https://www.theglobeandmail.com/glob...ticle11487709/
The four percent rule
For ordinary passenger vehicles, there’s no law in the U.S. that regulates speedometers, but U.S. manufacturers (and most Japanese as well) subscribe to a standard called SAE J1226. Your speedometer reading must be within a range of plus or minus four percent off, but that’s four percent over the entire range of the speedometer, and that range can then be shifted in what’s called a bias.Look at the above chart based on a Scion’s technical guide. At low speeds you’re potentially going faster than the speedometer says, but at 100 mph you’re going at least three miles per hour slower.
The European formula
Now it gets really crazy. The European Union requires adherence to UN ECE Regulation 39. It’s a lot of math, but the simple version is that no speedometer can read slower than the actual speed. Ever. On the high side, it’s allowed to read up to 10% above the actual speed plus four or six kilometers per hour, depending on the type of vehicle.Compare this chart to the first one. The most a speedometer can be off at that same 100 mph (160 kph) is nearly 13 mph. This is why many BMW and Porsche drivers notice their speedometer is off.
Last edited by C7_GrandSport_FTW; 04-14-2020 at 08:19 AM.
04-14-2020, 08:14 AM
#13
Drifting
Member Since: May 2002
Location: Great State Of Arkansas
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The Waze app uses GPS for position and speed if I'm not mistaken. If it works in your other vehicles, are you sure it's not the Corvette possibly reading high. Have you owned the car since new, does it still have the stock wheels and tires the car was assembled with?
04-14-2020, 08:18 AM
#14
It's within 1 mph of what the vette's speedo shows for me... Getting WAZE to always run is an issue, but I think that's my phones problem with how it handles the USB. Sometimes I have to set the phone to transfer data instead of just charge. Sometimes I have to be stopped with the parking brake engaged before it loads. Weird.
04-14-2020, 12:01 PM
#17
Safety Car
Both my truck and C7 have slightly different wheel setups then factory. Thus their speedo's are off by 3 to 4 MPH at highway speeds. The C7 is going slower then indicated (I swear officer) while my truck is actually going faster. The GPS in Waze was on the money when I had the factory setups.
Other then tire size maybe the GPS signal is getting blocked in the C7? I've had various mapping apps get confused due to large buildings or trees overhead. Try a different position for your phone as a quick test.
04-14-2020, 12:03 PM
#18
Tech Contributor
Member Since: Oct 1999
Location: Charlotte, NC (formerly Endicott, NY)
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How much of a difference is there? Is it possible the Vette's display is set to metric Vs English?
Bill
Bill
04-14-2020, 12:20 PM
#19
Drifting
Thread Starter
GPS speed as displayed in Waze will ALWAYS be lower than what the car is indicating. Speedo's always overread, some more than others. This is a known fact.
https://www.theglobeandmail.com/glob...ticle11487709/
Look at the above chart based on a Scion’s technical guide. At low speeds you’re potentially going faster than the speedometer says, but at 100 mph you’re going at least three miles per hour slower.
Compare this chart to the first one. The most a speedometer can be off at that same 100 mph (160 kph) is nearly 13 mph. This is why many BMW and Porsche drivers notice their speedometer is off.
https://www.theglobeandmail.com/glob...ticle11487709/
The four percent rule
For ordinary passenger vehicles, there’s no law in the U.S. that regulates speedometers, but U.S. manufacturers (and most Japanese as well) subscribe to a standard called SAE J1226. Your speedometer reading must be within a range of plus or minus four percent off, but that’s four percent over the entire range of the speedometer, and that range can then be shifted in what’s called a bias.Look at the above chart based on a Scion’s technical guide. At low speeds you’re potentially going faster than the speedometer says, but at 100 mph you’re going at least three miles per hour slower.
The European formula
Now it gets really crazy. The European Union requires adherence to UN ECE Regulation 39. It’s a lot of math, but the simple version is that no speedometer can read slower than the actual speed. Ever. On the high side, it’s allowed to read up to 10% above the actual speed plus four or six kilometers per hour, depending on the type of vehicle.Compare this chart to the first one. The most a speedometer can be off at that same 100 mph (160 kph) is nearly 13 mph. This is why many BMW and Porsche drivers notice their speedometer is off.
04-14-2020, 12:22 PM
#20
Drifting
Thread Starter