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I HAVE A 1996 PETERBILT 379 WITH WIRING ISSUE. PRIOR OWNER…

I HAVE A 1996...

I HAVE A 1996 PETERBILT 379 WITH WIRING ISSUE. PRIOR OWNER GOT CREATIVE. HE DIRECT WIRED FAN TO BE ON ALL THE TIME, THEN NEXT SHOP INSTALLED SWITCH FOR FOR FAN. EVERY TIME THE FAN IS TURNED ON IT BLOWS ACC FUSE. AS YOU KNOW IF THE FAN DOESNT WORK PROPERLY YOU HAVE ISSUES WITH YOUR A/C. IM IN NEED OF WIRE DIAGRAM FOR THE FUSE PANEL THAT HAS THE RELAY/FUSES FOR ENGINE FAN, WIRING DIAGRAM FOR THE SWITCH TO THE A/C COMPRESSOR ALSO ANY WIRING DIAGRAM FOR THE ENGINE FAN WOULD ALSO BE HELPFUL

Mechanic's Assistant: I'll do all I can to help. Can you tell me more about what's going on?

ENGINE FAN IS NOT COMING ON AUTOMATIC AND A/C COMPRESSOR HAS NO POWER

Mechanic's Assistant: What is the complete model and serial number of your machine?

1995 PETERBILT 379. LAST 8 OF THE VIN IS #TN382691 CAT-C15 ESN 5EK059549

Mechanic's Assistant: Is there anything else the Equipment Mechanic should know before I connect you? Rest assured that they'll be able to help you.

FAN WONT TURN ON AUTOMATIC. WHEN ENGINE TEMP 215 DEGREE OR A/C IS ON THE FAN WONT TURN ON WHEN HIGH SIDE PRESSURE OVER 250 PSI i HAVE TO TURN FAN SWITCH MANUAL SOMETIME FUSE BLOW WHEN FAN SWITCH TURNS ON AND PREVIOUS OWNER WENT TO FEW DIFFERENT SHOP TO FIX BYPASS BACK TO ***** SYSTEM TO MAKE FAN ONLY WILL WORK IF ENGINE TEMP IS A RIGHT TEMP. AND A/C COMPRESSOR DOES NOT WORK RIGHT. IM TRYING TO FIX OEM WIRE RIGHT WAY

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Answered in 4 days by:
9/8/2021
Technician: Daniel Wilson,
 replied 1 year ago
Daniel Wilson
Category: Medium and Heavy Trucks
Satisfied Customers: 14,846
Experience: Owner at DJ Wilson
Verified

Hi, My name is***** will be glad to try to help. We can follow up as needed on here. Professionals are not employees of the site but users of the site and help on here as time allows depending on their daily schedule.Sorry to hear you're having these troubles with this truck. Click on this link below to view the proper wire diagram for this engine fan circuit. It would be a good idea to have Caterpillar electronic technician connected as well to monitor fan parameters. Some are wired into the ECM where the ECM the fan as you can see mentioned in the diagrams I've provided. Others will run a separate fan circuit when not connected to the ECM.

https://www.dropbox.com/s/t0wys8smqglg3az/DIAGRAM-3406E%205ek.pdf?dl=0

I hope you find this information helpful. Reply back with the results of these checks if any further help is needed. It is a pleasure to help anyway I can.

Daniel Wilson
Category: Medium and Heavy Trucks
Satisfied Customers: 14,846
Experience: Owner at DJ Wilson
Verified
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Daniel Wilson
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Category: Medium and Heavy Trucks
Satisfied Customers: 14,846
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