I have a 2000 Disco II and keep getting the code 1562. I replaced the battery and had the aternator checked- it is putting out alittle over 13 volts- so the obvious problems are eliminated.
Often it will come on right at accelerating or when pulling my boat but it comes on at random times. Any ideas?

On a side note my water pump went out about a year ago, I replaced it (with a rebuilt), it went out again (I replaced it with a new one) and left the fan off. All through the spring and summer I have been running my rover without a fan without any over heating issues (except once while idling with the A/C on for over 10 minutes). I feel like an outlaw.

My guess on the 1562 is a short somewhere that suddenly draws alot of voltage setting of the fault code. What do you think?

 

Please put fan back on. Without a scanner to read the temps you are depending on the factory gauge, which is programmed to show normal for a very wide array of temps. You could easily be overheating or almost overheating and not know it. An earlier post this week showed pictures from an ultra gauge, 221 temp, and his factory gauge said normal. It is true you don't need fan on the highway, but you need it slow and idle.

1562 is triggered when tranny ECU sees less than 9 volts on the supply cable. Could be short (seems like it would blow fuse), oxidized connector (like a bad battery connector or other connectors on the way to tranny ECU), dead cell in battery (but you should be having cranking issues with that.

Attached drawing from RAVE shows 12 volt power from battery to underhood fuse box to F12 to Tranny ECU. Suspect that would be considered the supply line. Might try cleaning up every terminal in that path, and measuring from (-) battery to those points with a meter, certainly should be more like 14.2 volts with truck running. If you are just getting in the low 13's, your alternator may not be keeping up with the load. You could also have crud to clean up on other wire connectors and fuse links. 13.8 to 14.2 is about where you should be across the battery, at idle, nothing extra turned on. As you turn things on, it should not drop below say 13.2, with everything on.

 

You need to go get the charging system rechecked, the required voltage is from 13.6 to 14.4, anything else and you will have problems.