Still does not rule out a failing ignition switch causing this problem. If you do not have ABS problems at other times, I really do not think this is caused by the ABS system. The engine stumble and speedometer jumping along with the lights indicates that one of the ignition main power segments (ignition 1 or ignition 2) is dropping out. It affects different systems depending on which one it is.

 

Ya know I remember you mentioning that early on in my posts months ago....is the ignition switch a pretty easy swap.....how does the ignition switch going bad cause these problems? Never thought it could be that but right now I will take ANY advice I can get....Thanks a ton.....

 

It is fairly easy to replace. The book method is in the Tech Article (DIY) section and you can search on it to see the symptoms. This is a definite possibility with these trucks. The ignition switch controls power to everything in the vehicle. If it starts to drop one of the two main power paths to the rest of the systems, some VERY weird things can happen.

 

Wow...well its $72 from the 'Zone and I already found the thread on the replacement....does replacing the switch mean I'll need new keys or is it more internal than that?

 

Could it be coincidence that the same day it started losing power and stalling that the ABS light comes on? Any chance they could be associated?

 

You replace the switch, not the ignition lock cylinder. So no new keys.

I really think they are associated.

 

OK...Here is the reply I got from ModuleMaster asking if the erratic speedo could be caused by the module....

The erratic speedometer could either be a bad module or a bad rear wheel speed sensor (there's only one in the rear and it's located in your differential). If you have your module scanned, the error code(s) generated will indicate the problem. You can have this done at your dealer (at their hourly rate) or send it to us for the cost of shipping and we'll scan it for free. If there's nothing wrong with it, we'll send it back and just charge you for the shipping (around $8).

If your module is bad (a very good chance), our rebuild is $130. However, please make sure your module is one we can rebuild. The Blazer uses 3 types of modules shown here: http://modulemaster.com/en/abs/kh325_310_30.php

Thanks!
Will
ModuleMaster

Is there a way I can check the wheel speed sensor at home?

 

VSS is located in the back of the transfer case, not the differential.

I have never seen an ABS module screw with the speedo. Especially considering that it really has nothing to do with the signal from the VSS... It only reads it, not intercept...

 

Here is an interesting thread I found which describes my symptoms to a tee....


I have a 2000 Blazer LS, 2 door, 5 speed, 4x4.

Here are my symptoms:
1. "ABS" light and "E-brake" lights are on
2. speedometer and odometer quit working
3. Right after starting the blazer it has no acceleration power, it spits sputters and jumps. I have to hold the gas to the floor in order for her to come out of it, which it eventually does. This doesn't usually happen though if i let it warm up for 30 minutes though.

...the scanner read that there was a speed sensor malfunction. Do all these symptoms sound like they're being caused by the speed sensor? If they are all caused by the speed sensor, which one do I replace the "wheel speed sensor" or a regular "speed sensor" or is there a difference!? Thanks for the help everyone!!
__________________
2000 Chevy Blazer LS 4x4

So i removed the sensor today and found a pretty good sized chunk of fine shavings the size of a big pea globbed up on one side of the sensor.....not sure if this is the culprit or not? Cleaned it off with a rag and NOT air...( a static issue). Drove it 30 miles home at 65 mph with no problems. Maybe that glob affected the magnetic field of the sensor....I don't know at this point....I guess I'll drive it until the problem happens again.....

 

A dirty VSS can definitely cause some issues.