Hi everyone, so for years I've had rough shifting and running issues and after reading this forum decided to replace the PSOM. After replacing it with a rebuilt from Modular Mechanics the truck ran and shifted great but within hours the dreaded ABS & Brake warding lights came on. I checked all the fuses, all looked good, disconnected the battery, no change, so then decided to try and clear the ABS codes by grounding the two wire access plug under the dash that I've read so much about in the forum. The only problem is I grounded the PSOM connector under the glovebox and not the ABS module wires. F*@K !!!

After realizing what I did I started the truck and noticed that the odometer was blank. I then drove to work and the speedo is dead as well. So I pulled the rebuilt PSOM and put the old board back in. No change, odometer is still blank. I checked all the fuses and they all check out fine, especially fuse #8. So now I'm thinking I'm missing something. Does anyone have a diagram showing which fuse the PSOM diagnostic plug connects to ?

Thanks for the help.

Phil.

 

The PSOM programming wire doesn't connect to any fuse - it goes directly to the PSOM, and its only purpose is to be grounded. So grounding it will not hurt anything. But the PSOM uses more than 1 fuse. And those 2 warning lights coming on simultaneously do NOT indicate any fault in the ABS system, or codes to be read - they indicate low fluid in the reservoir. Read these pages & the links on them:

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You should also put ALL the truck's details & history (as much as you know) into your signature so it shows with each post, as this page explains:

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Phone apps don't always show signatures, so you may need to switch to a real browser in desktop mode on your phone, or just use a desktop/laptop computer. Put your location (nearest city) in your profile & upload an avatar of the truck. The more pics you post of the truck, engine, wiring, labels, & undercarriage, the more likely we can help you. Not all its details are relevant to these issues, but you don't necessarily know which ones are relevant, so just put everything in now.

 

Thanks Steve, yes, I forgot to mention that after I filled up the brake fluid the ABS and brake lights went off. However, both PSOM boards are dead in the water. I'll go through the fuses again and hoping I missed one. Will report back.