Drag, C0045 and C00560

[wormwood1978]

2008 Trailblazer, 120k, rust belt. Last night near home coming to a red light, felt drag. Leaving the light, felt a lot drag, little acceleration high rpms. Pulled over, turned off car, turned back on, normal again. No idiot lights. I was thinking brakes, hoping not transmission.

Scan tool said C0045 and C0050, left and right rear speed sensor misfunction. Cleared codes, test drive normal. Live data on the speed sensors all looked good.

If this reoccurs, what is the likely problem, troubleshooting? No car work in the last month, rear stabilizer bar bushings and rear control arms a few months ago. Wiring harness issue?

I'm a medium skilled DIYer.

 

[mrrsm]

Generic Diagnostic and Repair for GM & GMC Trucks sporting the C0045 and C0050 Rear Wheel Speed Sensor Codes ....but the important issues for the repair are well covered. Parts Purchasing as needed should of course dial in on JUST the 2008 GMT360s...

Follow THIS Dude's recommendations for How To Clean the Cast Iron Surfaces down to a *GLEAM* -- B4-- Re-Installing the ABS Anti-Locking Brakes Speed Sensors. Again... it's the Testing and Clean Up TECHNIQUES prior to the R&R that really matter here...

PS... From around 1;05 and briefly thereafter in the 1st Video... a political label image appears in the background that should not affect the quality of this repair information ...one way... or another.

 

[wormwood1978]

Thank you for the this but I'm skeptical about unnecessarily replacing both rear sensors. I could see if I'm getting a code for one side, then replace it. But both sides, I'm wondering if the problem is a wire or connector or the module, upstream from where the sensors come together and hit the module.

 

[mrrsm]

Most Likely Cause...? The "Rust Jacking" covered in the 2nd Video... it LIFTS the Plastic portion that fastens to the Cast Iron Hub just enough to break the Weak Magnetic Field being created by the internal rotating Reluctor Wheel ...just underneath the Speed Sensor Fine Coil Windings ...just enough to create an intermittent A/C Sine Wave... fooling the ABS Unit into thinking that the Wheels have Locked Up on top of "Black Ice..." or Wet Roads.

 

[budwich]

There appears to be a PIT for troubles in the coded area. (PIT 4594)
It deals with wiring issues in and around the air pump relay... broken / cut wires in the plastic conduit in the area.

 

[wormwood1978]

Update, now three drives and it hasn't repeated. Other than the single event yesterday that made me question it possibly being a transmission issue, I haven't had any transmission issues. I've had vehicles with transmission issues so I know what the common signs are. I'm thinking it might be a corroded wire, corroded connector, ground issue.....I ran my Autel scanner for 45 minutes on a drive looking at the live data associated with the wheel speed sensors, and there was nothing off.

 

[Mooseman]

Scan tool said C0045 and C0050, left and right rear speed sensor misfunction. Cleared codes, test drive normal. Live data on the speed sensors all looked good.

This tells me that a wire or ground common to both is going bad.

 

[wormwood1978]

I'm now four drives in since this happened and nothing more. I am now second guessing myself and wonder if I bumped the shifter putting it into D3. That might explain the drag. I don't think that is what happened but its possible. I'm not sure that would explain the rear speed codes though.

 

[mrrsm]

Since you are also posting this issue over at TV... This link (and PDF) will help to "Knit" these two pursuits together and help to keep us up-to-date on whatever their Members might figure out, too:

Drag and C0045 C0050, Speed Wheels Sensors

www.trailvoy.com