42rle solenoid block.

[OutdoorEd]

Hey guys.

So my 42rle has gone into limp mode. I’ve got a code P0700 generic code, but that is all.
My main question is, if the problem is a solenoid block, is this something that can go quite suddenly?

This thing has been running great for the 12 months I’ve owned it. I had an incident where I blew a radiator hose, engine is fine, and when I got it home I changed the hoses, water pump and thermostat. There is no blown head gasket, but within driving for 20 kms it has now got this transmission issue.
The timing of the transmission issue has me thinking the blown hose and subsequent overheating is the cause, but I can’t see how.
Unless some how the steam in the engine bay has damaged the ecu

Trans fluid level is correct at operating temperature.

 

[John Cooper]

Hey guys.

So my 42rle has gone into limp mode. I’ve got a code P0700 generic code, but that is all.
My main question is, if the problem is a solenoid block, is this something that can go quite suddenly?

This thing has been running great for the 12 months I’ve owned it. I had an incident where I blew a radiator hose, engine is fine, and when I got it home I changed the hoses, water pump and thermostat. There is no blown head gasket, but within driving for 20 kms it has now got this transmission issue.
The timing of the transmission issue has me thinking the blown hose and subsequent overheating is the cause, but I can’t see how.
Unless some how the steam in the engine bay has damaged the ecu

Trans fluid level is correct at operating temperature.

Check your transmission wiring harness on both sides and the top. When mine did that it was a rubbed wire on the passenger side.

Took 2 days to find it, by pretty much feeling the wires by hand because I didn't drop the transmission.

 

[JMT]

Hey guys.

So my 42rle has gone into limp mode. I’ve got a code P0700 generic code, but that is all.
My main question is, if the problem is a solenoid block, is this something that can go quite suddenly?

This thing has been running great for the 12 months I’ve owned it. I had an incident where I blew a radiator hose, engine is fine, and when I got it home I changed the hoses, water pump and thermostat. There is no blown head gasket, but within driving for 20 kms it has now got this transmission issue.
The timing of the transmission issue has me thinking the blown hose and subsequent overheating is the cause, but I can’t see how.
Unless some how the steam in the engine bay has damaged the ecu

Trans fluid level is correct at operating temperature.

How hot does the 42rle get? It can overheat pretty easily. If you don’t have a gauge you should probably get one. Is the fluid still good after the event?

 

[OutdoorEd]

Check your transmission wiring harness on both sides and the top. When mine did that it was a rubbed wire on the passenger side.

Took 2 days to find it, by pretty much feeling the wires by hand because I didn't drop the transmission.

View attachment 670978

Thanks John.
I’ll check this out, hopefully it’s as simple as that. Not that finding a rubbed wire is simple.

I had thought I had it fixed, I pulled the 4 plugs from the ecu and cleaned them with some electro clean. The next test drive it was fine, drove it about 15kms without a problem. Then the next drive it acted up again after about 5kms.

 

[JMT]

Thanks John.
I’ll check this out, hopefully it’s as simple as that. Not that finding a rubbed wire is simple.

I had thought I had it fixed, I pulled the 4 plugs from the ecu and cleaned them with some electro clean. The next test drive it was fine, drove it about 15kms without a problem. Then the next drive it acted up again after about 5kms.

Is it shifting fine before going into limp mode? A fluid change is a good starting point.

 

[OutdoorEd]

How hot does the 42rle get? It can overheat pretty easily. If you don’t have a gauge you should probably get one. Is the fluid still good after the event?

I’m in the process of getting a gauge. I changed the pan and filter a few weeks back, fluid was old.
This Jeep has hardly been wheeled, I bought it because it is an auto, I’m going to swap my axles and suspension into it from my 05 manual. Is easier than doing a transmission swap.

 

[OutdoorEd]

Is it shifting fine before going into limp mode? A fluid change is a good starting point.

It was running and shifting great, then out of nowhere it felt like it downshifted and went into limp mode.
When I cleaned the ecu connectors it drove and shifted great, right up until it went into limp again.

 

[John Cooper]

It was running and shifting great, then out of nowhere it felt like it downshifted and went into limp mode.
When I cleaned the ecu connectors it drove and shifted great, right up until it went into limp again.

How hot does the 42rle get? It can overheat pretty easily. If you don’t have a gauge you should probably get one. Is the fluid still good after the event?

@JMT possible ECU.???

@Wranglerfix Mark.?????