Bleeding brake lines on gm with ABS

radioman

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ARRGGGHH!! the title says it all. I blew the brake line for my second vehicle for rear brakes and I left it sitting there since last sept.

Well, with the weather is warmer now, I decided to work on 2 cars at once. I replaced front pads, calipers, rear drum pads, wheel cylinders and parking brake self adjusters on the first car. I was able to firm up the brake pedal by turning on ABS cycle 5 times after waiting 10 secs with key on/off. Thene Bleeded all 4 wheels in specific order perfect!! first car done. no problems! love the short pedal distance, nice and firm and stops nice and straight. All is good right?! I am happy so on to next vehicle.

I started on my blazer by jacking it up onto stands and remove rear tires and inspect everything. uh oh- rotors rusted, has scoring. pins frozen in calipers for both front and back. sigh.. more money. I could just suck it up and try cleaning it up and rebuild them, but the parts alone is only 10 bucks less then whole new calipers, so I forked over some serious wad for for 4 new calipers, got rotors turned, I was able to exchange my pads for warranty replacement and got new steel brake lines along with one rubber hose. I was able to replace everything with no issues and then started to bleed the lines. hmmmm , I got some bubbles, but not as much I thought I would. I thought I kinked the lines or didnt tighten the connections somewhere. I went back over every inch of line and everything seems to be in order.

Now what do I do?! I turned to google and found that my model of blazer requires a ABS scan tool to activate the darn abs pistons to purge the air from abs block. Or another option is to try to drive it and get the ABS to kick in and then try to bleed lines again. I just don't feel comfortable with that soft or near no brake pressure. Since the brake fluid was drained from rears leaking and replaced line from abs block, I know I have air in that block, but I dont have the EXPENSIVE abs scan tool so I can just bleed the darn ABS block so I can bleed the rest of lines. Does anyone have any ideas?!
 
I can't find any info on whether this tool allows you to run the ABS pump:



Amazon wants $67 for it.

Autozone sells it, not sure if they will loan you like they do with other tools....

If all else fails, you can have a brake shop bleed the system for you, probably will cost you the same as if you bought the tool yourself...
 
I hate Blazer's ABS bleeding procedure, you are correct about using a factory scan tool (TECH II) to activating the ABS pump motor to bleeding. But you can do manual bleeding by use special clamps to press the valves in the ABS hydraulic module (integrated pump motor). I fabbed my own clamp tools.

Any time you see Blazers or GM vehicles with ABS, you never clamp the piston down in the brake caliper for replacement brake pads. When clamp the piston you must open a bleeding screw to bleeding the fluid into a container while clamp the piston or allow the fluid go back to the hydraulic module and damage the hydraulic mechanical or seals, may be too hard to bleeding or replace used hydraulic module from the boneyard.
 
I can't find any info on whether this tool allows you to run the ABS pump:

Amazon.com: Actron CP9449 BrakeScan Anti Lock Brake System (ABS) Diagnostic Scan Tool: Automotive


Amazon wants $67 for it.

Autozone sells it, not sure if they will loan you like they do with other tools....

If all else fails, you can have a brake shop bleed the system for you, probably will cost you the same as if you bought the tool yourself...

No, they will not activate the ABS motors. Only read codes. You need $3K to $4K GM TECH II scan tool that can do anything around the GM vehicles, you can activate anything like check power lock/unlock function by use a factory scan tool
 
I did the Blazer bleeding procedure last abt 10 years ago without a scan tool. I lost my memory. I remmby I did bleeding the Cavailer or other GM (I can't recall), still low pedal after manual bleeding (installed new master cylinder) with the engine off. Frustrated but I decided to turn the engine running at idling, bleeding the corners (made my leg relaxed and easy to press the pedal slowly), at the end of the bleeding procedure, I got a good firm brake pedal. The shop manual doesn't say about the engine running while bleeding. Maybe you try it again. HTH
 
As you posted, try to take your car to driving on the grass surface (I don't know your place is) and play with the pedal as you like to pumping hard or quick pump as long as you take ur time then return to your place and do the manual bleeding. The slippery surface (grass or icy) helps the air pockets in the ABS box to purge out while pumping the pedal as the vehicle maneuver around the slippery surface. Not on the street along the vehicles around you. Be careful.
 
No, they will not activate the ABS motors. Only read codes. You need $3K to $4K GM TECH II scan tool that can do anything around the GM vehicles, you can activate anything like check power lock/unlock function by use a factory scan tool

You just confirmed my suspicions and it sucks to be me. :aw: I don't think 3-4 k will be worth the buy just for one vehicle with that issue.

I can't find any info on whether this tool allows you to run the ABS pump:

Amazon.com: Actron CP9449 BrakeScan Anti Lock Brake System (ABS) Diagnostic Scan Tool: Automotive


Amazon wants $67 for it.

Autozone sells it, not sure if they will loan you like they do with other tools....

If all else fails, you can have a brake shop bleed the system for you, probably will cost you the same as if you bought the tool yourself...

I looked into that tool you referred before I posted here and it will only read ABS codes and erase them. The manual doesnt say if it will activate the abs solenoids or not so I am assuming not.
 
just take it to mechanic
 
As you posted, try to take your car to driving on the grass surface (I don't know your place is) and play with the pedal as you like to pumping hard or quick pump as long as you take ur time then return to your place and do the manual bleeding. The slippery surface (grass or icy) helps the air pockets in the ABS box to purge out while pumping the pedal as the vehicle maneuver around the slippery surface. Not on the street along the vehicles around you. Be careful.

I thought that might work- but I have NO brake pressure so afraid to take it out. for a short drive. I havent tried it in driveway yet, it still in garage and I wanted to get less travel in brake pedal before I try that.
 
ARRGGGHH!! the title says it all. I blew the brake line for my second vehicle for rear brakes and I left it sitting there since last sept.

Well, with the weather is warmer now, I decided to work on 2 cars at once. I replaced front pads, calipers, rear drum pads, wheel cylinders and parking brake self adjusters on the first car. I was able to firm up the brake pedal by turning on ABS cycle 5 times after waiting 10 secs with key on/off. Thene Bleeded all 4 wheels in specific order perfect!! first car done. no problems! love the short pedal distance, nice and firm and stops nice and straight. All is good right?! I am happy so on to next vehicle.

I started on my blazer by jacking it up onto stands and remove rear tires and inspect everything. uh oh- rotors rusted, has scoring. pins frozen in calipers for both front and back. sigh.. more money. I could just suck it up and try cleaning it up and rebuild them, but the parts alone is only 10 bucks less then whole new calipers, so I forked over some serious wad for for 4 new calipers, got rotors turned, I was able to exchange my pads for warranty replacement and got new steel brake lines along with one rubber hose. I was able to replace everything with no issues and then started to bleed the lines. hmmmm , I got some bubbles, but not as much I thought I would. I thought I kinked the lines or didnt tighten the connections somewhere. I went back over every inch of line and everything seems to be in order.

Now what do I do?! I turned to google and found that my model of blazer requires a ABS scan tool to activate the darn abs pistons to purge the air from abs block. Or another option is to try to drive it and get the ABS to kick in and then try to bleed lines again. I just don't feel comfortable with that soft or near no brake pressure. Since the brake fluid was drained from rears leaking and replaced line from abs block, I know I have air in that block, but I dont have the EXPENSIVE abs scan tool so I can just bleed the darn ABS block so I can bleed the rest of lines. Does anyone have any ideas?!


Better way to take your SUV to GM dealership for bleed brake with ABS. It's cost you around $30-$50
 
No, they will not activate the ABS motors. Only read codes. You need $3K to $4K GM TECH II scan tool that can do anything around the GM vehicles, you can activate anything like check power lock/unlock function by use a factory scan tool

Correct, I used work for GM dealership before. Also must use Tech II AND SPX kent-moore for relearn TPMS on the Corvette, CTS, and other expensive GM.

$3k to $4k for outdated? That's silly and you can buy USED from ebay for $1k or less.


http://www.ebay.com/sch/i.html?_nkw...rom=R40&_osacat=0&_odkw=relearn+tpms+tool

You can buy brand New GM MDI for around $1,200. I love it and much better than Tech II. It's easy to reprogrammer thru online, better view, and fast even it's works great with Onstar. I prefer to use laptop with GM MDI over non-color tiny screen like Tech II. GM MDI must use Gmconnects.com for GM member only.
 
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Better way to take your SUV to GM dealership for bleed brake with ABS. It's cost you around $30-$50

yup. a very small price to pay for peace of mind. I don't bleed my brake myself. I only have one chance so it's best to leave it to professional for that unless you practice it well enough under supervision.
 
yup. a very small price to pay for peace of mind. I don't bleed my brake myself. I only have one chance so it's best to leave it to professional for that unless you practice it well enough under supervision.

I replaced the brand new rear calipers, rear pads, and rotors due old caliper got seize and locked up the wheel. Then I bleeding all manual bleeding then still not work then I take it to shop and it take 1 hour for $30. Same happen my old Subaru with ABS.
 
I did the Blazer bleeding procedure last abt 10 years ago without a scan tool. I lost my memory. I remmby I did bleeding the Cavailer or other GM (I can't recall), still low pedal after manual bleeding (installed new master cylinder) with the engine off. Frustrated but I decided to turn the engine running at idling, bleeding the corners (made my leg relaxed and easy to press the pedal slowly), at the end of the bleeding procedure, I got a good firm brake pedal. The shop manual doesn't say about the engine running while bleeding. Maybe you try it again. HTH

I tried manual bleeding with engine running for my old Subaru. No luck. So The shop did with ABS scan tool and it's works good.
 
I thought that might work- but I have NO brake pressure so afraid to take it out. for a short drive. I havent tried it in driveway yet, it still in garage and I wanted to get less travel in brake pedal before I try that.

Oh shoot....No worry abt it, I am here to helping you....
 
Better way to take your SUV to GM dealership for bleed brake with ABS. It's cost you around $30-$50

$30 to $50? No way in SoCal, they usually charge for over $100 labor per hour, plus fluid and more diagnositic time charge maybe over $200. Not cheap...
 
Correct, I used work for GM dealership before. Also must use Tech II AND SPX kent-moore for relearn TPMS on the Coretta, CTS, and other expensive GM.

$3k to $4k for outdated? That's silly and you can buy USED from ebay for $1k or less.


GM TECH II | eBay

You can buy brand New GM MDI for around $1,200. I love it and much better than Tech II. It's easy to reprogrammer thru online, better view, and fast even it's works great with Onstar. I prefer to use laptop with GM MDI over non-color tiny screen like Tech II. GM MDI must use Gmconnects.com for GM member only.

Oh no no no, please.... I advise you do not buy any GM TECH II scan tools from ebay because they are imported from China, they copied outdated software and cloned scan tools to market in worldwide, they will not support you for technicial problems. I've heard the stories from iATN forums. Only trust legitimated dealer such as AESwave.com (I use to shopping stuffs from AESwave), they can download update software (purchased new GM TECH II scan tools from the factory) for you if you buy it from AESwave.
 
$30 to $50? No way in SoCal, they usually charge for over $100 labor per hour, plus fluid and more diagnositic time charge maybe over $200. Not cheap...

Because I asked them for bleeding ONLY and I let them know that I bring the brand new fluid bottle in my car.

Everyone know that CA is so expensive for everything. Yes, you can find $30-$50 anywhere at IL and IA for bleeding only.

IL/IA's most shop are around $40 labor per hour. Cheap?

Oh no no no, please.... I advise you do not buy any GM TECH II scan tools from ebay because they are imported from China, they copied outdated software and cloned scan tools to market in worldwide, they will not support you for technicial problems. I've heard the stories from iATN forums. Only trust legitimated dealer such as AESwave.com (I use to shopping stuffs from AESwave), they can download update software (purchased new GM TECH II scan tools from the factory) for you if you buy it from AESwave.
 
I replaced the brand new rear calipers, rear pads, and rotors due old caliper got seize and locked up the wheel. Then I bleeding all manual bleeding then still not work then I take it to shop and it take 1 hour for $30. Same happen my old Subaru with ABS.

I recall the some Asian vehicles like Subaru or Isuzu if you bleed without scan tool, you must leave the vehicle on the ground. If the vehicle is about to lifting and remove the wheels for bleeding procedure, you have problem with no bleeds, unless you disconnect the linkage from the rear suspension's level control valve (looks like proprication valve). Weird design but I think they are for AWD and brake safety reason?? :dunno:
 
Oh no no no, please.... I advise you do not buy any GM TECH II scan tools from ebay because they are imported from China, they copied outdated software and cloned scan tools to market in worldwide, they will not support you for technicial problems. I've heard the stories from iATN forums. Only trust legitimated dealer such as AESwave.com (I use to shopping stuffs from AESwave), they can download update software (purchased new GM TECH II scan tools from the factory) for you if you buy it from AESwave.

Ah Thanks for a sharing, I don't plan buy TECH II anything because it's oudated and not works for most newer cars like OnStar and reprogrammer, So GM MDI is better and afford. I tried Tech II and GM MDI before. I love GM MDI more than Tech II.


I found it from AESwave.com that you trust it.

AESwave.com Store, lab scopes, scan tools, accessories and training for automotive diagnostic equipment!


For example, on a late-model Tahoe hybrid with 7 ECUs, it would normally take 2 full hours to reprogram with a Tech 2. But, with MDI the process can be completed in just 45 minutes. That's a 64% difference and means you could service 10 vehicles rather than 4 in an 8-hour day!

It's true.

Never buy outdate hardware because they are overprice and slow.
 
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