It may not be the most relevant of issues but no cruise control stopped me taking the DI on many long non-rover related trips. I had worked on this problem at several times. The whole system was rung out pin to pin, vacuum pump checked, relays checked, switches checked, cruise ecm swapped out to later D2/P38A unit, hoses, etc. Everything looked good. It held vacuum but just wouldn't work. Yesterday, I was driving the interstate into Virginia Beach wishing for cruise. The activation switch was pushed in and when I pulled back on the SET+, viola, I had cruise! It lasted about 30 seconds...damn. Tried it again and it worked for another short period. Only when I hit a bad bump did it drop out. I held the brake pedal up tight and tried again. It worked for as long as I held that pedal up. The switch, ERR2622, was opened, cleaned and it reinstalled. Nothing...damn it. I pulled a switch from another DI and swapped it out. I have cruise control! It will engage as low as 25 mph (which seems crazy) too. On top of that, I swapped in another door lock receiver module and repaired the matching fob so I also have remote door locks for the first time. It was a good day!
'99 DI cruise control fixed!
- Thread starter ezzzzzzz
- Start date
Nice! This will be something I keep in mind. I"m shipping mine back stateside and I'll need cruise working (or at least I'll want it a lot) then.
Reviving this thread since you mentioned ERR2622. Also in the process of fixing my CC system and found the switch masking taped all together. When I tried to push it back into place it pops right out when the brake rest. Does your switch have this problem? Or do I have a bad switch?
You probably have a poorly fitted aftermarket that doesnt want to fit the stock hole.
I just drove over 2000 mi without cruise control - would sure like to figure out why mine isn't working. Seems to have so many components I'm not sure where to start. Good to see that it CAN be done! 
Retrofit D2/Bosch P38 Cruise Control ECU into D1/GEMS P38
How to: Retrofit D2/Bosch P38 Cruise Control ECU into D1/GEMS P38 Below is the D1/GEMS P38 cruise control ECU. They're unreliable and fail often. This is a D2/Bosch P38 cruise control ECU with pigtail. They're cheap, abundant, and more reliable. Extract the guts.
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