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Discussion Starter #1
my pedal is spongy as hell. i replaced all the brakes and lines a few months back. im pretty sure i just need to bleed the abs unit. im trying to use the craftsman 20899 scantool. not sure if this unti will do auto bleed, but i can even get the unit to power up. is that normal to just have the SES light just blink a few times and go off?
 

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Discussion Starter #2
all i can get is the SES light on the dash flashes 3 times and pause's 5 times and repeat. the unit 20899 will not power up.
 

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1995 GMC Suburban
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94 truck is OBD-I (one).

Have you checked the FAQ?
 

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Discussion Starter #4
i have an OBD 1 scantool that wont power up when plugged in. im currently trying to find info but cant. thats why i posted. under what FAQ section? i dont seeing anything. i must have missed it
 

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Discussion Starter #5
in the faq section does nothing for me that i can see. i know how to read codes and i have a it all downlaoded for years but ive never needed it. but thats not what im trying to do at all i dont need to read codes or anything. im trying to bleed the abs unit to get a stiffer pedal.
 

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Discussion Starter #7
yea i could do that but the abs kicks in super quick in rain and makes me slide. im just wanna bleed this thing finally
 

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"yea i could do that but the abs kicks in super quick in rain and makes me slide. im just wanna bleed this thing finally"

Are the tires the original size that came with the truck? Had a similar problem with the abs on my '93 C2500 until I changed the jumpers on the VSSB. (Vehicle speed sensor buffer.)
 

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Forgot to mention I had put bigger tires on the truck.
 

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Ride down a dirt road and lock the breaks a few times always works for me.
I think that is what I found in the FAQ.
I have never read anything on using a scan tool for OBD-I truck.
It may be for OBD-II but even then it is questionable.

You may want to check the gasser truck forum (not here).
I suspect, the gasser truck have the same ABS as the diesel.
If you can use a scantool, they have a lot more sample.
 

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Discussion Starter #11
I think that is what I found in the FAQ.
I have never read anything on using a scan tool for OBD-I truck.
It may be for OBD-II but even then it is questionable.

You may want to check the gasser truck forum (not here).
I suspect, the gasser truck have the same ABS as the diesel.
If you can use a scantool, they have a lot more sample.
its likely ur correct. its justa strange situation. i have a obd 1 plug and the scan tool wont turn on and the SES light just blinks 3 and 5
 

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Discussion Starter #12
"yea i could do that but the abs kicks in super quick in rain and makes me slide. im just wanna bleed this thing finally"

Are the tires the original size that came with the truck? Had a similar problem with the abs on my '93 C2500 until I changed the jumpers on the VSSB. (Vehicle speed sensor buffer.)
[/Q
ive had the truck since 2014 in the late winter it use to stop on a dime no problem, break not spongy at all. had 32 or w.e. at the time. i bought it like that. now with all the brakes front rear all redone lines up to the abs unit. bleed them all till i got new fuild out. i just need to get a obd1 scan that can do auto bleed and i asked around so for people that dont know a snap on red brick or modis can do it. im digging for info. i need to figure this out asap. im sick of having this stupid problem. lol
 

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With my snapon solus scanner I have to apply 12v to the the adaptor for it to power up and and work. This is on a 95. 96+ I don't due to there being 12v at the port. 95 and older do not have a 12v power point like the 96+ do. This might be your problem to why you can't get anything from your scanner.
 

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Discussion Starter #14
the obd 1 scan tool 94 and 95 have the abs auto bleed systems.
With my snapon solus scanner I have to apply 12v to the the adaptor for it to power up and and work. This is on a 95. 96+ I don't due to there being 12v at the port. 95 and older do not have a 12v power point like the 96+ do. This might be your problem to why you can't get anything from your scanner.
how are u applying 12volt?
 

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SCTrailrider's advice worked for me on my son's 2000Chevy C3500. We had to replace a rear brake line that rusted through and no amount of bleeding gave us a good pedal. Took it down a gravel road and hammered the brakes into a skid many times and had a good solid pedal after.
 
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the obd 1 scan tool 94 and 95 have the abs auto bleed systems.

how are u applying 12volt?
On the side of my adapter there is a plug that you plug a cord in that either goes to the cigarette lighter or I have a another one that has 2 clamps on it that you can hook to the battery. I will see if I can find a picture of what I am talking about.
 

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s-l1600.jpg
the one on the left marked gm-1 there is a silver ring on the right side. That is where I apply 12v to it to make it work.
 

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Discussion Starter #18
yea the kit that i have doesnt have that silver side tab
 

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Discussion Starter #19
gm really made this a pain in the a$$
 

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gm really made this a pain in the a$$
well if it makes you feel better it wasnt just gm. every manufacturer had there own port pre 96. In 96 they had to standardize to one plug. And if I remember right you have to apply 12v to every one that was pre 96.
 
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