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new (to me) 05 XLR- won't start.

That should work, but the Helm manuals are $10 cheaper.

CC :wave:
 
At this price and by the mis-spellings in the website, I'd wager this is a cheap, Chinese clone. The only thing that's authentic is the pirated software on the 32Mb card.

That being said, as long as the vendor has a return policy, you're somewhat covered, but if it dies next year. . . As a self-described gambler, this ought to be right up your alley!

And as little as you'll need to use it, it ought to be helpful in peering at the innards of your XLR.

CC :wave:
 
I'll buy it and see what happens... For science!

I don't mind being a Guinea pig long as there's a decent chance of it going well, hah!

Thanks again!!
 
Sounds like you have your hands full, sorry I am no help here, I just though I would drop in and say Hi & Welcome to the forum! CC has helped bail many of us out in the past too (thanks CC for always being willing to help)

For 7 grand you got a steal but it going to test your patience too. If the car is in good condition running or not, it has to be worth twice that or better for parts...... not that I would ever suggest parting it out.......just saying!

Anyway, best of luck with the car: when you get it running you are going to love it - guaranteed! I will keep an eye on your progress, keep us posted. :burnout:[SUB][SUP]<strike>
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The Saga Continues...

So i waited for the clone tech2, and the service manuals to arrive. I plugged the scanner into the car and it wouldn't get any feedback from the car- BCM or otherwise; it does have a connection with the car, the light on the CaNdi module blinks.

I ordered a new BCM and installed it and I'm still at the same place.

what happens when i reconnect the (new) battery is this:

I the alarm goes off- or what the horn tries to pass off as an alarm sound.
A bunch of switching and clicking in the dashboard area.
The radio sounding like it cycling through CDs for about 30 seconds till it completes its cycle (I'm guessing).

The headlights work, and so does the fuel door release- otherwise everything else is dead.

When i put my foot not he brake and press the button to start, all that happens is some clicking sounds and thats it- nothing else

I've checked all the fuses- I haven't checked the relays, because i don't have a multimeter.


Ive checked the ground on the battery- are there any other places to check ground? I've looked all over and inspected what I could, but i don't want to dive in unplugging/plugging/connecting/reconnecting things blindly and add another issue to confuse my misguided diagnoses.

I refuse to take it to the dealership (though maybe i should)...



What would your next step be on this?


Thanks,
Ben
 
Ben,
I truly believe the battery is not fully charged......
ras


Sent from my iPhone using Tapatalk
 
Ben,
I truly believe the battery is not fully charged......
ras


Sent from my iPhone using Tapatalk


I should clarify- its not the clicking sound you'd generally hear from a dead battery- its more like clicking/flickering sounds from the dash.

Ive gone to the extend of buying a battery charger, and making sure the battery is fully charged as well.
 
Their are multiple grounds. I recommend if your going to work on the car get either the repair manuals. Either cd version,or paper backs. They have ALOT of repair procedures and all the specs needed.
If the car won't communicate bringing it to the dealer might be very costly trip,or they might know exactly where to look. :dunno: keep us informed and good luck.
 
Too bad I moved from El Dorado Hills Ben; I could have dropped by and taken a peek at your problem; it sounds like it would be a lot of fun to troubleshoot.

To start, it doesn't sound like your Tech 2 is communicating with the data bus. A steady blinking light on the CANDi module means it is functioning and receiving power.

Question: Are you able to get to the Vehicle Control Systems screen?

If not, the bus and Tech 2 aren't talking.

That brings up a couple of first checks to verify, --namely power and ground.

Are you confident in the (new) battery? Even with a charger, a defective battery may show proper voltage, but there won't be enough stored current to do any good. Establishing the integrity of the battery should be your #1 priority. While I'm inclined to think it's probably good, you have to keep an open mind to ALL possibilities when troubleshooting a tough problem.

If you want to work on your car yourself, I recommend keeping a log book and recording every action and symptom while you're eliminating suspected faulty areas. This will also be useful for the next person who works on the car if you have to take it to an expert. I've fixed a lot of systems that had prior work performed and the first thing I always do is ensure there aren't any faults added to the original problem by someone before me.

You'd be surprised how many loose connections, connectors not fully mated, and that sort of thing occur when someone who isn't methodical goes on a rampage trying to fix something when they have no clue what they're doing.

The car needs a thorough visual inspection followed by power distribution verification before you can start the component-level checks.

You stated you replaced the BCM with no change in symptoms. I don't know your troubleshooting skill level, but this car is too complex (and expensive to throw spares at) if you aren't sure of what you're doing. It's basically a four-wheeled, networked computer system with a really nice body.

The BCM's main function is to control power circuits to multiple modules, so it's an ideal place to monitor and gather a lot of information about the vehicle's status. The fact that the ignition switch is illuminated is useful, since the BCM routes power through it.

Lights and indicators are powerful troubleshooting aids if you understand how they relate to a circuit's operation.

You cannot effectively troubleshoot power and grounds (unless it's a visual fault if a cable/connection is damaged/scorched, open, or disconnected) without a multi-meter. They're an indispensable tool and can be purchased for less than the price of a BCM. --Besides, a multi-meter is useful for lots of other jobs around the house. My go-to meter is a Fluke Series 77; it will outlast me.

While you're looking for more symptoms to post here, have you inspected the rear/left compartment for water intrusion? If not, verify the drain line isn't obstructed, then using a bright light source, visually inspect the interior, noting any corrosion on connectors, and signs of a high water mark on the walls of the compartment, including sediment at the bottom. A short here can pull the bus low, and fry additional modules.

My guesstimate is one (or more) module on the bus are cooked, but you have to get the power distribution checks verified and comms restored with the Tech 2. You may need to disconnect modules before you can perform further symptom elaboration.

What do you know about the former life of this car? Is there a chance this is a flood-damaged vehicle? Have you obtained a Service History from a dealership? It's free, and very useful.

Manually retract the top; it will allow easy access to the car, and offer more light during the inspection process.

Big Picture Troubleshooting Path Forward:

1) Conduct a thorough visual inspection. Concentrate on wire harness looms (perform a hand-over-hand inspection) and connectors. Sniff around, your nose is a troubleshooting aid too!
2) Verify the operation of the Power Distribution network.
3) Establish comms with the Tech 2. -This may involve disconnecting non-priority modules to unlock the bus.
4) Restore the ignition sequence. This is tied in with ensuring the Easy Key system is functioning.
5) Add modules and verify proper sub-system operation methodically.

CC
 
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When your test gear doesn't give you answers, always question your test gear.

First thing I would do is find a car in the year range your tech 2 can connect with and try it on a known good car.

Second, visual inspection of the ODB port on the car, make sure no wires have come out the back of it.

You have no idea how many times I've tried to troubleshoot a problem only to eventually check my test gear, finding out it was some connector not pushed in well, or some bad connector on the test equipment.
 
Ben,

David brings up a very good point that I overlooked regarding your (new) Chinese clone Tech 2. Have you tested it on an applicable year GM vehicle other than your XLR? As long as it's getting 12 volts, the Tech 2 title screen with software rev should appear. Does it?

CC :wave:
 
Ben,

David brings up a very good point that I overlooked regarding your (new) Chinese clone Tech 2. Have you tested it on an applicable year GM vehicle other than your XLR? As long as it's getting 12 volts, the Tech 2 title screen with software rev should appear. Does it?

CC :wave:

You have received lots of good information. The following is much more time consuming and you need to be confident of what is going on if you want to try it, these notes are offered for you to use at your own risk. You need the full workshop manual to locate every module on each data bus.

Trying to diagnose a fault like yours at long range is tricky. The symptoms seem consistent with a fault on a data bus, it is not unknown for something to short it out, usually to ground but it could be to high. I haven't tried this on the XLR but I have tried it on other data buses, and that is to use a volt meter on the signal pin, with the other to ground. You need to be on the DC range and you should see something that isn't 0 volts nor is it 5v. The AC range should also give you a non zero result. If you have a scope you can look for the signal. This will give you a clue that there is at least a signal. You need a good quality meter with a high internal resistance.

If there is no signal, you need to unplug as much as you can easily get to (ALWAYS battery disconnected when plugging or unplugging). Ideally it would be everything, including the BCM. Once everything is unplugged take a voltage measurement to check that you haven't got a 12v signal (but you should know this from earlier). If you have 12v find the short to voltage. If you have a very low resistance to ground, you have a short to ground, which you need to find. If you haven't removed everything, this low resistance to ground check is not a reliable test. However, you should get to the point where there is no short to voltage or ground. If you don't pass, unplug more. If you do pass, plug one equipment at a time back in until the signal stops. The first module in is the BCM. If you unplug some modules and then get a working data bus, you have a clue where the fault lies.

You could work the other way round, unplugging one module at a time until you get a signal, but if you have multiple faulty modules it is harder to work out which are causing problems. Keep adding (good) modules, checking each step of the way that that signal is still on the data bus.

To be efficient, unplugging everything and then putting half back at a time is the least number of steps, however, given the time taken to plug and unplug modules it could be easier to work one at a time and hope it is one that is easier to get at which has the fault.

Take detailed notes. Once you have a suspect module, unplug and plug it to confirm that the fault appears and disappears, you need strong confirmation. Be aware that more than one module could be defective.
 
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I would add this.

When something goes wrong, sometimes it's not from natural causes, but from "something changing".

For instance, of your sprinklers stop working somewhere, you could look where you know the lines run and see if maybe the Wife/husband planted something right on top of where you know the sprinkler line goes.

So, on your car, you could start by looking for anything unusual. open the doors the trunk the hood, look for anything that doesn't look locked down. Maybe a wire that's flopping around with it's attachment point flopping free in the air.

Look at pinch points, where the door closes, where the hood closes, where the trunk closes, etc.

Anything after market installed? Unplug it if you can.

If you know the car was in an accident, try looking in the area of the repair. A repair done improperly that didn't route a wiring harness correctly, or tie it down, or had some damage that wasn't repaired can cause problems eventually.
 
Okay, so i took in everyone's feedback and i went back to the basics. I jacked up the car on all corners, i reconnected everything to replicate the day i bought the car. Tested the battery (it was fine), but went any bought another one anyway because everyone keeps chanting battery battery battery.

The tech2 would refuse to communicate with the car said something along the lines "onstar/vcim not communicating with vehicle", and it made me think that since its a clone it doesn't work right (read plenty about this issue). I unplugged the battery and went back to the fuses. every single fuse seemed fine the first time around but i went through it again- the 10amp (iirc) on-star fuse on the new BCM was blown. I replaced it with another one and plugged the battery back in. clicked the button to start the car and same issue- flickering sounds behind the dash, tech2 refusing to communicate-even though its powered via obd2 port. I went to look at the 10amp onstar fuse again and as i pulled it out the car decided to turn on just like that... the fuse was blown- but now the car is on. the tech2 communicates with everything though it still says "onstar/vcim not communicating..." except for the trunk module and the stability control module (there was water in that compartment- so theyre fried I'm sure). I turn the car back off, check all the fluids to make sure everything is okay, and start it back up again and let it warm up.

The shift select refuses to budge, and according the the DTC the brake sensor needs calibration.
Every DTC error under the sun was showing. I reset everything one by one to see which is lingering behind- but thats more for tomorrow.

One extra issue at hand though- The trunk unlatches and lets me pick lift it about 1 foot before it stops moving (and i don't want to force it too much for fear of breaking something- but if theres another 'oomph' i should do, let me know!). I looked at the hardtop and its not completely closed- almost as if it stopped working right when completing the cycle to close fully (the top isn't latched closed-you can open it with your hand slightly)
I feel like the trunk won't open unless the roof has completed it's cycle and is either fully open, or fully closed. I grabbed a tool to latch it shut manually, but it won't budge, and i don't want to force it either.
if there are any suggestions for this, i would appreciate that as well!

Today was a large victory- I know the car at least turns on- I feel I can tackle everything with the combination of the tech2, the service manuals, and you guys as a resource! :cool:
 
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That's good news. The brake pedal position issue will prevent the car from starting and transmission shift lever from moving unless you manually lift the solenoid-operated latch pawl. Make the pedal issue the first priority repair/adjustment. This also indicates the Easy Key subsystem is operational.

Your header latch problem can be caused by multiple possibilities. A faulty FTC module, a failed solenoid valve, a bad position switch, or a mechanical issue in the latch itself. It can be manually open/closed with the top tool with the plastic access cover removed as shown in the Owner's manual. With the folding top raised, I'd cycle the mechanical assembly with the tool to eliminate mechanical binding, then verify switch operation at the FTC module connector. After that, it's likely the module is causing the problem followed by a bad solenoid. As always, there may be multiple faults.

Without the FTC module to control the appropriate solenoid valve (#4) on the hydraulic header, the rear deck lid is tough to move due to hydraulic pressure. You can try to command the solenoid manually, but if the module is fried, it isn't likely to operate. Keep pressure (the cardio-pulmonary kind) on the rear deck lid until you get it raised, then open the hydraulic bypass valve, which will allow you to stow/raise the top manually and with a lot less effort.

Since you described water intrusion, I would disconnect both the FTC and Suspension Control modules and leave them off the data bus. Before installing replacement modules, thoroughly clean and inspect the connectors and conductors for corrosion - it can creep under the insulation too.

Neither module is related to the ignition circuit and you can eliminate them from any other data buss issues for now. The VCIM needs to be disconnected as well so you can troubleshoot the short on the power distribution network. Obviously, the open fuse does that too, but I'd keep the module out until you get the short issue resolved. The module may still be operational.

Does this vehicle have a branded title?

CC :wave:
 
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Fabulous! Thank you.
It's a clean title car. I bought it from the second owner who used it as a commuter car between Sacramento and San Francisco for the last 5 years- you get a cookie if you can guess the miles on it! He had the car repainted to match his m5. He said he was going to fix the hardtop/suspension issue but then the car totally died in him- I'm going
to make a not so giant leap here and say that's when his mechanic gave him a crazy estimate to fix the car (and I think he had no real clue either- told me the alternator was dead: and it's fine) and there he decided to jump ship and sell.
 
As the old saying goes . . . "One man's loss is another man's gain." Good for you!

CC :wave:
 
normally , when car is running and in PARK, you have to press the brake pedal to shift into Drive or Reverse.
there is a distinct clicking from the shifter, the solenoid lock mechanism, that will click when you press the brake pedal.
you can press the pedal 3 times and hear the click 3 times.
solenoid lock can be manually flicked to open if you remove the center console cover.
i WOULD NOT drive this car until you get the top fully positioned and latched, either up or down.

could be just water damage from trunk leaking, but look around closely under floor carpets inside engine compartment
see if theres signs of actual flood damage. my bet is the car is fine, just electrical gremlins from the trunk comp. flooded.
you have a garage to store the XLR in once you get it fixed right ? ;)
 

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