Cruise control always 1mph above limit?

Forum for Engine, Exhaust, Drivetrain, ECU
biggster
Posts: 82
Joined: Sun Aug 31, 2014 8:04 am

Post by biggster »

The reason why speedometers can be out by so much is because they effectively measure he rotational speed of a wheel. However, because the diameter of a tyre changes slightly from new to worn out (the tread is worn away), the distance travelled by the wheel varies as well. Therefore, the speedometer will not usually show the exact speed of the car.biggster2014-09-02 06:38:54
Pearl Black 1.5dci Tekna - Chrome Mirrors, Chrome Door Strips, Chrome Front lip finisher, Chrome Lower Boot Strip, Mats...

ShinyAndy
Posts: 165
Joined: Tue Jun 10, 2014 7:13 pm

Post by ShinyAndy »

The OP is about the fact that if you set your cruise control to, say, 60mph then when you look at your speed on the digital speedo it will be 61mph - not inaccuracies with the speedo itself! This is a problem with the cars software
Adrian
Posts: 98
Joined: Mon May 05, 2014 7:27 pm

Post by Adrian »

Indeed it was, thanks for the course correction Andy!
2014 1.6dci Tekna Storm White 2WD
F1 Bob
Posts: 546
Joined: Sat Mar 22, 2014 12:26 pm

Post by F1 Bob »

Yes, mine is 1mph out. If it is set for 60 mph speedo shows 61 but not too bothered. I have also checked the speedo against GPS and speedo reads 3 mph over the GPS, So if speedo is saying n70 the actual speed per GPS is 67. I believe this is normal with all cars.
Pulsar 1.5 dCi Tekna in Bronze
Adrian
Posts: 98
Joined: Mon May 05, 2014 7:27 pm

Post by Adrian »

Yes, mine was the same until I had the ECU remapped and now it's actually doing the speed I set it at (with the normal discrepancy as is the norm if comparing with GPS etc)
2014 1.6dci Tekna Storm White 2WD
Kentishman
Posts: 237
Joined: Tue Jun 10, 2014 11:54 am

Post by Kentishman »

My speedo shows the speed I set on the cruise control for. Only variation as it adjusts for inclines up or down when it rapidly takes it back to the set speed
Tekna 1.6 CVT Nightshade
ShinyAndy
Posts: 165
Joined: Tue Jun 10, 2014 7:13 pm

Post by ShinyAndy »

Is that on the digital speedo (when enabled) on the info panel between the speedo/rev counter?
Kentishman
Posts: 237
Joined: Tue Jun 10, 2014 11:54 am

Post by Kentishman »

That's on the digital speedo. I don't understand why in this day they still use a large dial with a needle swinging back and forth from which your supposed to tell what speed your doing. Two small displays could replace those big dials.
Tekna 1.6 CVT Nightshade
biggster
Posts: 82
Joined: Sun Aug 31, 2014 8:04 am

Post by biggster »

[quote="Kentishman"]That's on the digital speedo. I don't understand why in this day they still use a large dial with a needle swinging back and forth from which your supposed to tell what speed your doing. Two small displays could replace those big dials.[/QUOTE]
Analogue dials are very good at helping to visualise your acceleration, where digital readouts are not - especially because the refresh rate of the digital speedos can be so low.Plus they do the cool dance when the car starts up!
Pearl Black 1.5dci Tekna - Chrome Mirrors, Chrome Door Strips, Chrome Front lip finisher, Chrome Lower Boot Strip, Mats...
ShinyAndy
Posts: 165
Joined: Tue Jun 10, 2014 7:13 pm

Post by ShinyAndy »

Maybe you got a newer build , assume you don't have the hesitation either?
Post Reply