[InTitusville]

So, the power from the 40A fuse under the hood goes through the BCM then to the ignition switch or does the ignition switch power come from someplace else? If it's the BCM where is it and how do I know it's bad. It's no bid deal for me to replace it but need to know what I'm replacing will get power to the ignition switch. I know the dash works since I put power to it last night and was able to get the odometer and some of the dash indicator lights to come on.

I may try to put power to the ignition switch connector (RUN) output wires today and see if the accessories work. If the accessories work does that rule out the BCM?

 

[InTitusville]

I put power to CAV 3 and 5 pins on the cable and the power windows, roof and radio work. The odometer doesn't come on (tested good when I force powered up the instrument cluster) and the overhead console don't work. I still don't have power to CAV 2 and 4 pins on the cable. I double checked the 40A fuse under the hood and the power to that fuse and both are good. Is there anything else that could be between that 40A fuse and the power to the ignition switch?

BTW... The radio does keep main power. If I turn the ACC power on and off the radio keeps the station but if I pull the battery power under the hood the radio looses the station.

 

[InTitusville]

Fuses 21, 22 and 31 look good. I can't understand why the 40A fuses is good and power to it. Unless there is something between the fuse and the ignition switch it should work. The 4.7l has head gasket issues or more so I'm taking the engine apart this week and that will give me more room to inspect the wiring. Maybe there's a broken wire someplace or maybe I will trace it to something between the 40A fuse and the ignition switch. Stay tuned... If someone does know of anything there please let me know...

 

[InTitusville]

I did some digging and digging and found some ignition diagrams. Then I found some used harnesses on ebay and I can see the under hood fuse panel is a "right side" engine compartment harness. Looks like the power for the ignition come off that harness and goes through the firewall and behind the A/C assembly. Looks like I will need to pull the whole dash apart to pull the A/C assembly out to trace the wires.

Now... This brings us the question in another post I have up... I want to change over from a manual climate control to the dual zone climate control and if I do all this work I'm already most of the way there and need to know if the 2 style climate control under dash harnesses are compatible with the rest of the harnesses in the rest of the Cherokee. I may just try to do the conversion and trace the wires all in the same job.

 

[InTitusville]

I checked both 40A fuses for power to the PK/BK and RD wires and both fuses are good and the box has power to both fuses but I have no power at the C1 point. I assume where is says C106 and C200 are connectors and I assume that part of harness are under the dash. I think my next step is to follow the electrical issue is to follow this under the dash harness. I also assume to access this cable I need to pull out the dash and A/C system. The head gaskets are bad so I'm taking the engine apart so might as wall go for taking the interior apart.

BTW... I LOVE that diagrams... Where do you find stuff like that???

 

[InTitusville]

This was the diagram I found.

 

[InTitusville]

I don't mind knowing going in to this there is an issue with the "blend door". I restore 1967 to 1973 Mustang and Cougar in-dash A/C systems and have had to deal with modifications to design problems. I've done over 300 of these A/C units. I know there's a huge difference but I'm sure I can come up with a work around. What is the exact problem with these doors and can I do the conversion with just changing out the A/C & Heater box, harness and controller? From what I see on the 2001 Grand Cherokee you need to take the dash out just to replace the heater core.

In the past I had owned 2 1980 Cherokees, a 1995 Grand Cherokee and we purchase a 1999 Grand Cherokee new.

Don't do the dual zone conversion. That system is not built well and will fail at the blend door and blend door actuator over time. It can be fixed with like parts but fails again. It can be fixed for good with the "heater treater' but it takes away the dual zone feature.

 

[InTitusville]

If you need your in-dash A/C box restored let me know. After restoring over 300 of them I know them inside and out...

This 2001 Grand Cherokee has 84600 miles on it, not bad for 18 years. It has this ignition issue which looks to be between the under hood fuses to the ignition switch which looks like I need to find the firewall connector and test it there and to get to that I need to pull the dash and the A/C system so I may just upgrade the A/C system and try to find a fix for the blend door problem.

(I have a 69 Cougar 'vert!)
It is at KTL right now...