huggabean Posted October 16, 2018 Share Posted October 16, 2018 I'm running a 1995 CL700 with an E7-400. Yesterday it developed a serious engine miss with major power loss. After changing fuel filters and inspecting what I could, I took it to a local shop. The mechanic discovered that the jake was staying on and disconnected it at the head. Truck works fine, but no jake of course. He said it was likely a shorted dash control switch, but I wondered why the miss would continue below 800 RPM where it always has automatically shut off if that were the problem. I re-connected the wires at the head and disconnected the switch, but the miss was back. Then with the engine running (and missing) I disconnected the wires at the head. Removing the back wire made no difference, but when removed the front one the engine idled and revved normally. There was a noticeable arc when removing the front wire, but none when removing the back wire. Additionally leaving the back wire on, the front one off, and re-connecting the switch didn't activate the jake in any switch position. The engine harness looks very good and not oil soaked or chafed and the connectors are tight. Any suggestions? Thanks Ed Quote Link to comment https://www.bigmacktrucks.com/topic/54573-jake-wont-shut-off/ Share on other sites More sharing options...
Mack Technician Posted October 16, 2018 Share Posted October 16, 2018 Hook it all back up and swap engine brake relays. 2 Quote Link to comment https://www.bigmacktrucks.com/topic/54573-jake-wont-shut-off/#findComment-408031 Share on other sites More sharing options...
Hobert62 Posted October 17, 2018 Share Posted October 17, 2018 1 hour ago, Mack Technician said: Hook it all back up and swap engine brake relays. I ran a ch years ago and same thing. Relay went bad. If I remember right it was in glovebox area. Quote Link to comment https://www.bigmacktrucks.com/topic/54573-jake-wont-shut-off/#findComment-408046 Share on other sites More sharing options...
huggabean Posted October 17, 2018 Author Share Posted October 17, 2018 22 hours ago, Mack Technician said: Hook it all back up and swap engine brake relays. Yes! That worked fine. Thank you so much Ed Quote Link to comment https://www.bigmacktrucks.com/topic/54573-jake-wont-shut-off/#findComment-408083 Share on other sites More sharing options...
Mack Technician Posted October 18, 2018 Share Posted October 18, 2018 2 hours ago, huggabean said: Yes! That worked fine. Thank you so much Ed Kudos Ed! ~Jason Quote Link to comment https://www.bigmacktrucks.com/topic/54573-jake-wont-shut-off/#findComment-408091 Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.