Diagnosing electrical bug - Please help

Hey All,

Was hoping someone would be able to help diagnose the problem with my 2000 Grand Cherokee Laredo.

I have a bunch of electrical symptoms that came up at the same time, which leads me to believe they are caused by the same root problem:

1) When using the fob to lock/unlock, the lights don't flash and the horn doesn't sound.
2) The overhead console displays information but the numbers are always null ie: where I should see "20.0 mpg" I instead see "-.- mpg".
3) If I open the driver-side door while the car is running, the overhead displays "Driver Side Door Open" but when I close the door that indicator doesn't go away.
4) The dial next to the one that controls the headlights, the one that is supposed to control the brightness of the dashboard lights, doesn't. Instead, the dash lights are bright, the radio lights are dim, and any adjustment to the knob turns on all the interior cabin lights in the car.
5) Sometimes while driving the interior cabin lights will randomly flicker on and off when they are not on.

I'm sure there are other weird things that I haven't discovered yet. Any ideas what could be causing all this? Thanks in advance for the help.

 

Welcome! The symptoms you posted could be a possible T.I.P.M. (total integrated power module) failure. That Chrysler module is making the news as a wide spread issue being reported by owners. Some have gone as far to say the vehicle is "possessed". Start by getting and posting any codes with a DTC reader or scan tool. There is not likely to be any cheap fixes especially when out of warranty.

 

this is A 2000 Grand Cherokee Laredo?

I seriously doubt it is a TIPM issue, so we can dismiss that.

Second the horn should never chirp when using key fob - lights flash OK.

nothing plugged into DLC/ALDL?
Troubleshooting:
Check all fuses underhood and in cab.
No recent repairs or work on vehicle? ANYTHING
Tell us jeep is STOCK no aftermarket BS - powertrain?
Scan for codes. use SCANNER.

...........................................................................................................................................................
Initiate the EVIC self-diagnostic test as follows:
(1) With the ignition switch in the Off position,
simultaneously depress and hold the C/T button and
the Reset button.
(2) Turn the ignition switch to the On position.
(3) Continue to hold both buttons depressed until
the EVIC software version information is displayed,
then release both buttons.
(4) Following completion of these tests, the EVIC
module will display one of the following messages: tell us what it says.


I would run the above test,
Then try a Hail Mary if system and fuses test ok, Remove the IOD fuse for a ten count and replace- this will reset (reboot) the BCM.

 

Welcome to the forum.
I am a complete moron when it comes to electrical issues. More knowledgeable members have given some great advice above. Post up your fix @pmangels17

 

Thanks for the help! It is all stock (minus a new radiator and high pressure power steering hose, but neither of those should affect electrical). I will try the test early next week as I have commitments this weekend that will keep me out of the garage.

 

• So, I removed and tested fuses 7 (interior Lights),17 (instrument cluster amd diagnostics), and 28 (body control module, acc/run) inside the car, plus the PCM, ECM, and a couple other fuses under the hood (one of which looked like it might not have been seated right) and jiggled the cable harnesses going into the box behind the coolant reservoir, and that did the trick seemingly! Maybe pulling the PCM battery fuse reset it or something. Fingers crossed!

 

Thanks for the advice and help everyone!