LH 2.4 does indeed have a limp home function if the signal is lost from the AMM. The AMM wire has to basically fry to enable limp home mode, which is why we have to manually disconnect the AMM to force limp home mode in cases where we want to isolate the AMM as the cause of a no start and indeed be able to limp home. It's not documented in the LH 2.4 manual that the loss of any other signal forces limp home mode, such as loss of the O2 sensor, block temp sensor, or EGR, which makes sense as these aren't critical for starting and running. The TPS and CPS on the other hand are critical and couldn't be programmed around if their signal was lost. In limp home mode the ECU uses a pre-programmed injector duration. Acceleration will be poor and the engine will badly stumble at moderately higher rpm, which some have attributed to an rpm governor function, but it's simply self-limiting fuel starvation.

Having all those breakout connectors would certainly be handy at times. Wow, a breakout connector for the ECU. I'm trying to imagine what it looks like. I can imagine it being handy for attaching an oscilloscope, but otherwise for multimeter use may not give you much better access than probing at the side of the ECU connector.
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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now