Detroit 60 Series DDEC

Needing help resetting 'Warn Eng" light on the Series 60 (DDEC II?). Background: I have a 1993 motor, 11.1L in my International. I've been slowly going through and getting things fixed. Truck runs great, pulls strong until around 2000rpm. When the engine warms up, I get the dreaded "Warn" light and my max rpm goes to something like 1600rpm and it is pretty miserable to drive. What is the best way to reset the check eng light? As far as I can tell, the many codes it spits out when I check the diagnostic are not actual problems.

For example, it gives codes 15 and 16, 23 and 24 which as far as I can tell are contradictory (high voltage and low voltage).

Not sure what triggers it because I don't know how the computer goes from all is well to 'oh oh' mode. Would appreciate any pointers. Thanks

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OK. First one is 14 which I'm not seeing in the DDEC II lists (still looking and reading).

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OK that worked great. Didn't get to go for a full drive but will try again tomorrow AM. I unplugged the sensor that lives on coolant manifold (for lack of a better term) and the truck ran perfect during my 15 or so min drive. Definitely up to temp and definitely beyond the 8 min barrier which typically sets the light off. So much easier to drive this thing with full power. Will try again and report back. Thanks @Big Road Skateboard !

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Thanks @Bean Jr.

I think I already replaced that low coolant sensor but good to double check. I never got a full shutdown, just lower RPM limit (and maybe less power?) which is annoying as F when you're loaded.

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OK so that did not work great. I got the truck up to temp and eventually I got the Warn light and the reduction in RPM.

Tried unplugging and driving with pretty much all sensors I can get my hands on but all eventually get to the RPM reduction. Coolant reservoir instantly lit up the stop engine (red light) along with the yellow. Some of the others held out for a bit longer but eventually all ended up with the RPM reduction. Weirdly, the RPM reduction only happens while the truck is moving. If I idle it up to temp, either with sensors unplugged or plugged, it shows the Warn (yellow) light but there's no limit on the revs. Our of gear it revs all the way up to 1950 (or really close to 2000 RPM) no problem.

Thoughts?

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Progress!

I had a backup oil pressure sensor and I swapped it. Still getting the Warn light but the truck runs normal past the 8 min mark and even when it is at normal temperature.

Still getting all the same codes (14, 15, 16, etc) but at least it runs properly. WTF is going on with this thing? LOL

I will work on the Pro Link angle.

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