1991 Cadillac Deville Codes

1991 CADILLAC DEVILLE
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WHITECAD
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  • 4 POSTS
Transmission problem
1991 Cadillac Deville Two Wheel Drive 158000 miles

I stopped at an auto parts house they checked the codes for my service engine light. It's 39 TCC fault & also a 40 Power Steering switch circuit open.
Now what?
Jul 21, 2010 at 2:51 PM
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RASMATAZ
  • CAR REPAIR CONTRIBUTOR
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Hi whitecad, Welcome to 2carpros and TY for the donation

Lets try clearing the code and see what happens

Clearing PCM Trouble Codes
PCM trouble codes stored in memory may be cleared (erased) by entering diagnostic mode (see ENTERING SELF-DIAGNOSTICS) and simultaneously depressing OFF and HI buttons on ECCP until "E.O.O" appears.
After the "E.O.O" display appears, release buttons and ".7.0" will appear. With ".7.0" displayed, turn ignition off for at least 15 seconds. Codes are now cleared.
Jul 21, 2010 at 6:58 PM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.