I have a 2004 f250 with a 5.4 and the abs light comes on when it is in park and you press the gas down hard or if you are going down the road and accelerating hard or going up hill also when the abs light comes on the speedometer goes to 0 and then back up also the transmissions glitches some times when it happens and the light under the hood flickers when in park and idling. Just trying to tell you everything I know):
You need a higher level scan tool to check the live data and analyze them.
Can you scan the car for any codes & post them here? ABS systems are incredibly complex.
It may be a wheel speed sensor which has gone bad, but the trouble codes will put you in the right direction.
@inthrustwetrust
I took it to a shop and they said there was no codes and could not find what the problem was. I replace the speed sensor in the back but did nothing but it will do it when its in park and you just press the gas hard so I think some kind of electrical. Like I said before the light under the hood flickers but inside the cab they do not. I replace the alternator think it could be causing it. Any help would be great.
@Hwahl
The fact that the ABS light turned on means the computer has saved a trouble code. I think the shop where you took it aren’t very good. Take it to any Autozone, they scan codes for free. Get the codes & post them here as it’s incredibly difficult to diagnose ABS problems just by description. The codes will tell you if it’s just a sensor that has gone bad or if the abs module itself is bad.
Alternatively, take your car to another reputed mechanic who has good reviews from your friends and check if they can diagnose it.
Can you make a video of the problem & post the link here?
@inthrustwetrust
What they told me was the abs is more sensitive then the main computer so it might not show any codes and I had my brother test it too and no codes. I'll do a video and give you a link. I don't even no if it is the abs or something else and the abs is just pick it up. Thanks for the help!
@inthrustwetrust
Here is the video.
https://www.youtube.com/watch?v=lFdMo3kYK7A
@Hwahl
Thanks for the excellent symptoms video!
You may want to have a read through this - https://www.thedieselstop.com/threads/intermittent-speedometer-and-abs-light.242847/?__cf_chl_captcha_tk__=9a7a0f02763a9ee05d911f557d6863b0f843e295-1606223682-0-AULeNLKOkYYJOc3kQCodFEObQnV2b8y-z7FqxMs65GpGhcDVdfiAQBbokKuWejMVCcTh_3WkkjG33p6K_CQG0MJ6oXY7YqQC_Tqct9XXdg1CIemaVtNEkumLeKam35y0hRwhy7if7e2fQEbAf8u5305orIxxHKD9nMLJg6PUJTRGgwwwUBLb5txKhyf_o0egCge9jEikVdHi4zQaVbtlWGKjJIcGfYAwLEiv3zn2jwvW2z6LmQoDy7yp-r22iVl-C4JEgmCP3auwN_MluE9kYRxo5ZbRrYdbyio1BFkKvB0-yKn-oi31OeEd6LOxPYj9TI4g61t6BIcLkdIlJ30fhZqgGWq9rswB6kyqJCxIiyAOBj_S9r9xTkWOiLKnznqHst_wIzlYUKlGw2QWUUijeZQPj2KruuKkzxSVOTAZpE543KNB8YDgL64_HtnINoAonNvi4XITzpquL_mhrVWpxTuztdz49voeQQYObogq4n7CIDvDFl9RLHQik8QEEdgmf5ziyFmE-OS-h_YU1q8Q-jEtahC4xHrbKQq8zqhe3MgoM1bmw_Cs-5G6EY9QEkDfUwDwxDysmuuaHX8YEt_xEaYjhLji1nsw4UbcScw3b8arKhiuto9U9qzFBY32qM_E75Ux4_Cjk5pd_NhSbmeNZDM
@inthrustwetrust
I found that same thing. I don't think it is the tone ring because it does it in park. The wiring off the back censer all goes in to a whole bundle of wires that is all taped up. Do you think it could be the abs abs module or the trucks computer?
@Hwahl
I think it’s the vehicle speed sensor which is providing incorrect data. If it’s not that, it may well be the ABS module itself or the main computer gone bad. But the VSS will be a cheap fix, compared to what you’ll have to spend for a new abs module/ECU.
Try to find a guy like Scotty who has a dealer level scan tool which can diagnose ABS faults. I don’t think any regular scan tool will be of much help to you.
Possibly engine torque is pulling on the wiring harness under the hood.
Check engine mounts.
You could pull on the underhood engine harness and see if you can mimic the problem.
@bc-st
I looked and could not tell anything. I don't know if you saw the video of the problem but here it is.
https://youtu.be/lFdMo3kYK7A