ABS shows 2 history codes with the Genisys, U1000 and C0042 R/F sensor circuit low. (Our Tech2 only goes to 2001)

I'm more worried about the U1000.


This is our service truck for the shop and people have complained about low speed ABS activation/pulsation in the front. Last night, it came back with the L/F wheel smoking/hot. Guess they had to use the fire extinguisher on it when they got back.

If it'* always the same caliper that is dragging, I'd condemn the caliper.

If the dragging caliper is a different wheel at different times I'd condemn the hydroboost.

Has the brake system been bled in a while?

I'm thinking the ABS has something to do with it. I drove it around the parking lot today and got the low speed braking pulsation to start. Coincides with the ABS kicking on. Then it seems like it stays on. Doesn't look like I will be working on this today...other bigger fish to fry...got a truck in here today running on straight kerosene and its not good for the DPF/SCR system.

Pulsation like warped rotor or like ABS?

Why kerosene? Does it live in Cuba or something?

No, at low speed braking you can feel the ABS pump kick on and start pulsating the front brakes. Then you let go, and it stays on for awhile. This is nothing like warped rotor pulsation.

Some truck companies believe its ok to cut diesel with kerosene. Sometimes they think its cheaper to run a truck on straight diesel. Until they get the $14,000 bill for new injectors and a DPF filter.

Ah okay. Almost sounds like the sensor on that wheel is marginally bad and not continuously seeing the reluctor ring and thinking that wheel has locked up. Weird thing is that this condition would cause the smoking pads on the same corner just driving around. I'm thinking the marginal sensor became more marginal after the assembly got really hot after a separate dragging-caliper issue . . . ? I'm curious how this comes out.

"Straight Diesel" is the non-low-sulpher stuff, right?

If "yes" then yeah totally see the problem.

So there are companies out there mixing kerosene with diesel? Do they do it in their big tank on the mothership or do they do it by filling the tank in halfsies? . . . or do they do it Dom DeLuise style in Cannonball run and just stick both nozzles in at once?

ABS computer is showing a code for the R/F sensor, but the L/F brakes got hot.

Regular pump diesel is Ultra Low Sulfur. These guys have what looks like white kerosene. 99%.

Wow. Yeah, it isn't 1990 any more. Diesels have changed.

Someone else worked on it, but they did say the L/F caliper pins were pretty tight which wouldn't allow the caliper to move at all. So they replaced everything on that wheel and replaced the R/F ABS sensor.

Still another ongoing issue, pedal will go halfway to the floor before brakes start to grab, but even standing on it, vehicle 'feels' like it will never stop.

Cool, sounds like normal stuff.

Sounds like master cylinder is sad.

Is the hydroboost under load when this is happening?