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Peterbilt ISX engine engine brake stopped working think it's…

Customer Question
Peterbilt ISX engine engine...

Peterbilt ISX engine engine brake stopped working think it's just a relay or fuse but do not have diagram

Mechanic's Assistant: What's the make/model/year of your truck? Engine type?

2009 pb 387

Mechanic's Assistant: Are you fixing your truck yourself? What have you tried so far?

Yes and nothing yet just quit working light went off on dash switch also

Submitted: 10 months ago.Category: Medium and Heavy Trucks
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Answered in 1 hour by:
9/28/2017
Technician: Daniel Wilson,
 replied 10 months ago
Daniel Wilson
Category: Medium and Heavy Trucks
Satisfied Customers: 6,898
Experience: Owner at DJ Wilson
Verified

Hi my name is***** will be glad to help. What do you have for fault codes logged in the ECM memory?

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Technician: Daniel Wilson,
 replied 10 months ago

I have some diagrams if you would be interested let me know.

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Customer reply replied 10 months ago
No codes I am an owner operator the other night the light went out for the engine brake switch and the 1-2-3 adjustment switch then I noticed the brake wasn't working going down hill I opened the fuse panel under the hood but there is no diagram showing which fuse is what all I need to know is where the fuse or relay is located then I can go from there I honestly think that is the issue thanks
Technician: Daniel Wilson,
 replied 10 months ago

The engine brake runs through the ECM on this one. Click this link for the ECM pinout to help. Check the wiring and connector pins for damage. Click below

Troubleshooting

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