1997 XK8
Will not start - just the tip of iceberg

What Works ( has power) -
Seat controls
Dash lights and system/startup engine check
Interior door lights
Radio
AC fan
Windows drop upon opening door

Whats not working (no power) -
Turn key to start position - nothing (no click or noise of any kind)
Window switches (except for drop on opening door)
Convertible top switch (no noise at all)
Door locks
Lights - Front or Rear
Turn Signals
Wipers
Shifter will not move from Park
OBDII code reader can't connect to ECU

What was checked -
Battery - Full Charge
High Power Protection Module
Power to all 5 Fuse/Relay boxes
Swapped all relays
Pulled and checked all fuses
Reset inertia switch

System Startup Check shows Hood Open and Washer Fluid Low
Neither are true but both are new with the electrical problem

Car was running fine, moved to different building (200 ft) cut of engine and found all the above issues 2 days later when I tried to start it.

Any help would be much appreciated.

 

How did you check the battery? Sure sounds like a power fault and battery is usually the problem.

 

My first thought is also Battery followed by the cables to and from the High Power Protection Module.

It's possible there's a Key Transponder Module fault where it's failing to pair with the Ignition key chip. When this happens, the key can turn normally through to the start position because it's the right cut but the ignition stays locked out. I've come across this on an X300 which has a similar security setup.

Graham

 

The US version '97 doesn't have a transponder.

 

I use a digital multi-meter for volts and ohms to test battery and fuses. The High Power Protection Module has same voltage on every stud and same voltage on cable connection point to each fuse box (12.88 volts). Also did a master reset with battery leads.

 

Check your grounds. Especially the main braided one.

 

My initial thought to your opening post was to be that "Battery - Fully Charged" is a meaningless concept on these cars . . . all that matters is the standing battery voltage as MEASURED well after any re-charge so that there is no residual float charge that would give a false reading. However, your later assurance of 12.88V saves the day.

Let me hazard a guess that you measured across the battery posts? If so, and in any event, you must now start checking for looseness or corrosion at each of the many ground connections. Why? Because like others here who have seen so many hundreds of similar problems . . . I also suspect general power failure.

I suggest you use your DVM and wiring diagrams to identify and check all fuses and relays . . . and focus on the permanent B+ circuits like lights. Then, move on to the ignition switch circuits, check keyhole shutter plate, the park/neutral interlock etc until you get engine cranking ("starting" is irrelevant at this point). Only by tracking each circuit to its final "ground seeking" connection, can you solve such a mish-mash of electrical woes.

Best wishes,

Ken

 

Jimmy, are you messing with me or am I just clueless. I started to take the braided engine ground off from the engine and realized when the bolt was loose that it was impossible to remove the bolt or cable because it hits the exhaust before clearing the bolt hole. I cleaned it while loose but still wedged between exhaust and engine. Bolt to body no problem, but made no difference, same missing power to half the car.

 

Ken,

I think all the issues are related. Running fine cut off, restart couple days later and power missing to half the cars electrical circuits. I'm not familiar with a keyhole shutter plate, can you enlighten me?

 

Actually, I was speaking of the main braided ground cable from the battery to the body. I know it sounds ridiculous, but I had a similar problem and was stuck at a subway garage. Some things came on, but no sound from ignition key. I called the wife to bring a jump and while I was waiting I grabbed the ground strap and just about burned the cr@p out of myself. I moved it around and bingo, started right up. Later I replaced the braided strap with a big solid honker. I've heard of people soldering where the crimp meets the braid. Just a thought ...

 

Hi.

Both the braided negative cable and and the red positive cable from the battery have known to deteriorate without any visible signs.

Also the battery clamps are thin walled and not very rugged.

Measuring volts without any load show normal values.
My positive red cable became very hot with lights on and engine off.

Also a braided ground underneath the car is very exposed to the elements.

 

Both Jimmy and Oyster mention the braided ground from battery to body. Mine may have been changed. Both ground and hot cables look heavy duty. I disconnected all grounds to body in the trunk (3) all very clean. I attached pics of battery cables and High Power Protection Module cables.The extra wires to battery posts are from my Tender Charger.

 

I also have video of dash lights when I try to start engine,

 

Wow!...my '06 did this once about two days ago. Got into car as normal, turned key to start and nothing...nada...zip. Tried to turning to start several times, and got nothing. Turned key to OFF, removed key, gave key a half turn, re-inserted key into ignition and engine started normally.

So I would think your problem is something to do with how the key is read. Perhaps give the key a good cleaning with alcohol and try again.

Good luck.

 

Have you tried doing a hard reset of the battery? Come across this a few times, doing this will reset all the modules, sorta like rebooting your computer at home. Try this and see what happens, then we'll have to go from here.

 

Lanny,

Key is different in 97, will only go in front or back (turn 180 degrees). I did clean and put in backwards, no difference. Thanks for trying.

 

Yes, pulled both leads from battery and shorted together for 30 sec. No difference. I still think its a single problem causing the power loss. As stated in the first post:

What Works ( has power) -
Seat controls
Dash lights and system/startup engine check
Interior door lights
Radio
AC fan
Windows drop upon opening door

Whats not working (no power) -
Turn key to start position - nothing (no click or noise of any kind)
Window switches (except for drop on opening door)
Convertible top switch (no noise at all)
Door locks
Lights - Front or Rear
Turn Signals
Wipers
Shifter will not move from Park
OBDII code reader can't connect to ECU

 

Wesley,
I think the key style is the same for your '97 and my '06 and I did not think there was anything on the key like GM used (resistor pellet) so was a complete "shot in the dark" with the "clean the key" comment.

Had you tried a different key? Although to me as long as the key turns in the ignition I do not see how a different key would make any difference, unless there is something within the plastic at the end of the key. IDK

I am going to follow this thread though since I had that one event.

 

Maybe this will help. See attachment.

 

Ok that attachment didn't work, trying again...