I'm new, and definitely not a mechanic

As I said, I’m not a mechanic, but I like to tinker and if it’s possible to do things myself I try to do it that way because if you don’t try you don’t learn.

That being said I have a 01 chevy blazer with a few issues. I just got it recently and it’s had these problems before I got it.

Brakes: the abs light is on. I have replaced the master cylinder with a used one but it works. The front was redone before I got it (rotors, pads, calipers, lines). The rear were sticky so I worked the caliper on the driver side and got it working as it should, passenger side I replaced because the piston was so bad it really wasn’t worth risking. Before replacing the caliper the light was on but the brakes were working decent. I changed the caliper and bled it several times to make sure I wasn’t getting any air. The brakes still work but are very soft and almost hit the floor with little force. I thought since the line sat open overnight it might have drained a little fluid from the other side so I bled it too. And for good measure, since I bought an extra bottle of fluid anyway, I bled the front again as well. Still soft and the light is still on. Saw a post recommending bleeding while running, but I’ve never had to do that or heard of anyone else doing it.

Transmission (4x4 4l60e): The transmission was replaced with a used one by the previous owner. I know the person well and trust him at his word. He said the trans worked good but I don’t know if it actually saw pavement after install. He was fixing it to drive and then got something better and it sat for a year or two just being moved around occasionally. First and second shift fine but no third or fourth. I was told it could be an issue where the brake system is telling the computer you are stopping and the computer is not letting the trans shift. I also remember growing up hearing stories about how bad 4l60s were.

Any idea what else I should look for with the brakes (vacuum, electrical, what else could cause it, does bleeding it while running actually make a difference)??

Does the abs system actually affect the transmission shifting or should I just go ahead and look for a new trans to put in it?

I feel bad asking for advice as I have nothing to really offer in return to the community, but I have read thru several posts here and the people here seem like good people so I figured it was worth a shot. Thank you for any help and advice you can give.

When you replaced the master, did you bench bleed it first before installing it? Try loosening the each line right at the master while a helper presses on the brake pedal. Then go around and bleed each corner again. If that doesn’t get it, the ABS may need to be cycled to burp the air out of it. That requires a scan tool that is capable of doing that. Don’t bleed while running. It won’t help, as far as I know.

Side note: repalce ALL of the rubber hoses at the axle and wheels. All of them. They fail and act like a sticking caliper. They don’t last 19 years on GM trucks.

I know of no ABS error that would prevent a 3-4 shift. I know of many 4L60E’s that fail the 3-4 shift pack.

A factory level scan tool is required the bleed the ABS anytime the brake system is opened to replace a component.


Thank you guys. The master was bled on install. That was changed when I got it because of the abs light being on. Driving it around some I noticed it took some effort to get it going sometimes which is why I changed the one caliper and worked the other free. It doesn’t seem to be dragging anymore so it seems that helped but the spongy pedal started when I changed the caliper. Guess I will start looking for a trans and someone to install it. Another question, on the side of the trans is the park/reverse sensor. The wiring for one of the plugs didn’t seem to be in very well, so I pulled it out and noticed the connector seemed to be covered in a glaze like substance. It’s not the gel stuff for electrical connectors, or if it is it definitely dried out. It made the plastic hard and shiny in spots almost like a clear coat paint accidentally overstayed on it. I can’t see inside the terminal on the sensor but the connector looks like a couple of the pin terminals are covered by this hard stuff and the connector doesn’t seem to me like it’s seating all the way in. That being said, what are the chances the harness could be in rough shape elsewhere and causing it not to shift.

I know I’m asking a lot for a sight unseen diagnosis but I’ve been out of work for over 2 months from back surgery and still have a couple weeks before I can go back so funds are limited.

It would be helpful if you could get the ABS and transmission codes read and post them here.

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No offense, but that was the wrong approach

The amber abs light won’t come on because of the master cylinder

You need to get the abs codes read . . . it could be a code related to the stop lamp switch, or maybe the abs hydraulic unit, the abs control unit, and so forth

Speaking from professional experience . . . there’s a very good chance the reason the amber abs light is on is because you need a new/rebuilt abs control unit

I’m saying this because we used have tons of S-10 4x4 4.3 blazers at work. And most of them eventually did need abs control units

But don’t replace it just because I suggested it . . . get those code(s) read and tell us what they were, please

Not shifting into 3rd and 4th almost certainly has nothing to do with the brake system. It could be a bad shift solenoid, a bad internal wiring harness . . . fairly common on these . . . or something along those lines. More than likely, you have at least one stored fault code relating to the automatic transmission

I’d use electrical contact cleaner . . . the stuff in the spray can that you buy at an auto parts store . . . and go to work on those terminals


I will see what I can do. I think my boss has a code reader and if not I may be able to limp it to the parts house and back.

I was going off some advice from other non mechanic but more knowledgeable friends. Plus it was free and the one I put on was known to be good.

I’ll try this and hope it helps. The way the stuff looked I don’t know if it will clean off. It looked almost like a hardened film over some of the pin holes.

Again, thank you guys.

It has to be a code reader capable of reading abs codes

if you get the codes read, don’t let anybody interpret the code(s) . . . just write down the code and report back to us, please

Well, I don’t know what else to do. Boss said he doesn’t have one, and the local o’reilly doesn’t have the machine anymore because of covid. Guess I’m kinda stuck until I get the money to either buy an obd2 scanner or pay a shop to look over it. I’m going to ask around and see if anyone else I know has one If I can find one I will update with the codes.

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Last time I was at the GM dealer, I think the price for a diagnosis was about $135. Not a great investment. I tried AZ in the past but to read all of the codes, the equipment is in the $20-30,000 range, that the dealer uses.

I have an Actron code reader that reads ABS and transmission codes. They are over $200 now. Has been great for DIYers. Maybe someone knows of cheaper ones, or just do a search for ABS and transmission capable readers. If you are going to delve into auto maintenance and repair it’s a good investment.

This is the one I have. It paid for itself the one and only time I had an ABS code. It was only $62 when I bought it in 2017.

Sorry it took so long but I’m back with more questions and less answers… I ordered a bluetooth obd2 from eBay, took forever to get shipped from NJ to KY but it finally arrived. But I don’t think it is getting power, as my phone can’t find it. The reason I went with no power over defective chinese product is because there are only 4 wires running to the obd port on the dash. Is there supposed to be only 4 or did I waste money on the scan tool.

There is a fuse for the power to the data link connector, it may be the same fuse used for the cigarette lighter.

I’ll check… also I started and ran the truck just a couple weeks ago,as I have been doing to keep it from just sitting, with no problems. Now it turns fine but won’t actually fire. I’m about ready to put a bullet in it,but I would rather have it running. I really like the style of these.



These codes are the ones showing in the system. Power train and transfer case. If I click health test it would take quite a few screenshot to show the codes, but I’m assuming that is because it’s not running and not actually able to test them. Guess I need to check the plugs and wires…

And thanks nevada, it was the fuse.

Ok, so I have not been able to do much with it lately because of the weather. But I got today off work and it’s beautiful out. So I put gas in it just for good measure because the gauge is broken… turns out that it was apparently out of gas… fired right up with a jump. From there I pulled the codes after taking it for a short ride up the road… I’m attaching 2 screenshots. In the readout I pulled it’s showing misfire is in cylinder one so I am going to pull the plug and see if it’s fouled and clean it to see if it makes a difference. If so I will get new ones for all 6. Otherwise I have no idea what to do. Hopefully someone will have an idea where to start.

Sorry I missed a screenshot… here’s the 3rd one… it’s the main one and I missed it…