In-cab switch for speed limiter?

Activate the driver rewards in the ecm. If plugged in the reader will show a governed speed of say 65. But you can set the parameters so you will always be a "rewarded driver" and it will give you the extra speed.

 

With the way ECM's are set up it's not possible to just make a switch to change the speed limiter, data has to actually be written to the ECM to change the speed limiter.

 

I'm confused here. You want a switch to activate or deactivate the speed gov in your truck?

Why not just have the speed gov turned off? Why have it on at all if you intend to turn it off?

Is this your truck,.. or does it belong to another carrier?

Hurst

 

If this is a company truck, not going to happen. You will not find a shop to turn up the truck. Now, most of these "road guys" won;t do it either. Detroit, Cummins, Paccar all 3 now have on their ECMs of who was in that ECM and when. I can pull up the last 10 connections and even go as far back as to the first program connection on that ECM with the settings I have. International, the junk engines they are, have a anti-tamper set up that even those that plug in a handheld will leave dust on the module. If the software is licensed, it will have the license number and the owner can report that the licensed connected to the truck without authorization and have your license turned off. Shops or those with licensed software will not take that chance,

As far as running a switch, that is also a not going to happen. Reason is most trucks are "multi-plexed" meaning several different signals (reference voltages) are going through the same wire from various sensors and in certain patterns. If you interrupt that signal by installing a wire and changing the voltage patterns by adding in the resistance from that wire, you will code out and then possibly get a "hard code" to set in the EVM, MCM, VCU (all depending on the truck) and you can kiss your job good bye. Not only your job, but possibly a career for an employer can report "tampered with safety equipment" as a reason and you'll be screwed.

 

The bully dog cannot adjust it on the fly. Engine must be off. Key in on position, rpms=0. I have the expensive hdgt.

 

The Safety Pass Pro simply alters the voltage to the vehicle speed sensor.. you can do the same thing with a dimmer switch, weatherpack plug, and some wire, and not spend $250+ for that POS... which isn't going to work on current production trucks, anyhow - it only works on trucks which use an analog signal.

 

Changing voltage does nothing to adjust speed signal, you cannot used a dimmer switch, I've know people who've tried and failed. To change the speed that the ECM see's, you need to change the frequency. Almost all vehicle speed sensors are analog, the ECM converts it to a digital signal. The VSS is nothing more than a magnet in a coil. When the teeth of the tone ring passes it, a small A/C voltage is produced. The ECM uses the frequency of that to determine wheel speed. Higher or lower voltage will change nothing expect cause a VSS fault if it cannot produce enough voltage to get a signal. You can alter voltage with the air gap, but that only changes amplitude not frequency.

Safety Pas Pro changes the frequency to fool the ECM to thinking that it's going slower than it really is. The reason this does not work on many newer trucks is that they compare wheel based speed from the ABS system to transmission output speed. If the difference is too much, the ECM decides which is more likely and uses it. 4 ABS sensors that match overrides 1 oddball vehicle speed sensor, so you'll get a check engine for a VSS fault and the speedo and speed limiter keep on working using the ABS system as it's source.

 

You are dead on GrapeApe!

What some of the fleets I have worked on are partnering with shops at the borders to do the top speed adjust, enter Canada and do your delivery/pickup, then return to the US and then return to the shop for the top speed adjustment.

Canada is a pain and that is why a lot of fleets are going there less and less while the large fleets are gobbling up all the freight. I quit going to Canada in my driving days a long time ago because of the hassles. I drove a 72 mph truck and wasn't cutting it down to 65 for them. I'm like most people in saying that other countries shouldn;t dictate what I do in my country. That is why I also quit going to California and then just sold the truck for the whole industry became too much of a pain.