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ABS Light, no code - EBCM?

Impala131

Impala131

New member
Hello again, all.

So on the new (to me) 98 GTP, it had both airbag lights and ABS lights. I couldn't pull any codes for either with my scan tool. (Palmer ScanXL, with Elm 327 bluetooth connector.) I have scanned and found ABS codes on a couple of different 2004 Impalas, and a Monte Carlo, so I'm 90% sure it should find the codes here, but not 100%

Anyway, I replaced the airbag module with an ebay unit quite cheaply (old one had the classic corrosion from the blower motor water intrusion). SRS system is fixed.

So, when I key on, the light comes on solid and immediately. No flashing, no going out and then coming back. It is on constantly from the moment the key is turned to ON. It doesn't go out for anything. But no codes. With my voltmeter, I tested the pins of the module connector... the two red wires are delivering power, and the pink wire (which I believe is ignition signal) is getting power. Checked that all fuses were good as well, particularly the A/C / ABS fuse under the hood. Connector pins are in great shape on both sides of the module.

I've read that this module (Bosch 5.3?) is pretty common to fail, but I haven't had it on one of my cars before. Is it pretty safe to say that my module is shot, since it won't feed back any codes, or do I really need to get another scan tool and try again? I feel like I should at least be getting a code from the BCM saying that it can't communicate with the EBCM, but I'm really not positive. Thoughts?
 


I'd check the ABS wire harness at the front bearings. Likely one (or both) of them are corroded or broken which will set the ABS light. Or you have a bad hub bearing. You can test the hub by sticking a voltmeter on the leads coming from the bearing and spin the tire. If you generate any voltage then that bearing is good and then time to check the harness. I think the 98 has the 2-piece harness on it. It follows the control arm and goes up towards the rad. support.
 
98 abs info like you are looking for is not in the pcm, it's in the body or abs modules. HPT wouldn't give me anything until about 2000. Then it's in pcm.
 
Sh*t guys, major f-up in my description. It's a 2003 GTP. I have no idea why I said 98. I'd fix OP but for some reason, I'm having issues editing it. It just gives me a blank box.

And I have repaired the wiring harness to the hubs before on other models...but those generate a specific code, and usually the ABS light goes out, then comes back on. At least, from my recollection that's the case.

I have HPT also...think I should try to find ABS codes with that as well?
 
SOLVED

So for some reason, my year EBCM is goofy and almost no scanners will detect or pull a code from it. I assumed the module was bad, so I sent it out for repair. Had the module promptly returned as they didn't find any problems with it.

Gave up trying to use a scan tool, and simply looked up the wiring diagram for the ABS to check every connection with a multimeter. Fordman77 was correct, classic broken wires to one of the hubs. Easy fix with some new wiring, soldering, and heat shrink.

Still dunno why the abs scan tools wouldn't pull a code (serial data pin on module connector has continuity with OBD2 connector so I assume it has to do with protocol.) A tech 2 probably would have worked, but I only had more basic ones at my disposal that seemed to work on other modules.

Also, I'm happy with the service I got from cheapabs.com. They tested it honestly and only charged me for the return shipping. Would definitely use them again for abs issues.
 
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