Jeep (WJ) Grand Cherokee won’t start? Stalls + Key Light + No Gauges

Автокөліктер мен көлік құралдары

Diagnosing a 2001 Jeep Grand Cherokee Laredo 4.0L that wont stay running.
p1686
Time Line:
00:00 - 00:50 demonstrate the problem
00:50 - 01:45 With SKIM unplugged
0:145 - 03:05 PCI bus works demo door locks & console
03:05 - 03:50 Door locks
03:50 - 05:15 5v sensors
05:15 - 06:10 Load testing SKIM power and ground wires
06:10 - 07:40 PCI bus diagnostic connector
07:40 - 08:10 oscilloscope on the PCI bus wire (not shown)
08:10 - 09:25 inside fuse box, BCM and data port location
09:25 - 10:40 Disabling SKIM VS replacing computer
10:40 - 11:15 What the dealer tech discovered
11:15 - 12:57 where the computer is located & one last thing I checked
PCM = Powertrain Control Module
BCM = Body Control Module
TCM = Transmission Control Module
SKIM = Sentry Key Immobilizer Module
Things to check
Door wires:
These Jeeps tend to break wires going to the doors, the door locks talk on the pci bus so issues with these modules or the wires going to them could potentially cause this issue
Bulk Head connectors:
next to the BCM (drivers side behind fuse box) there are several bulk head connectors, there are several more on the passenger side. These connectors have a bolt though them. to check for corrosion of the connectors.
Fuses:
there is a fuse box under the dashboard on the drivers side as well as one by the battery under the hood, check the fuses.
PCM / BCM connector corrosion:
unplug the connectors to the BCM and PCM and check for corrosion.
5V sensors:
Some of the 5v sensors on the engine use the same 5v rail as the PCI bus, if any of these sensors go bad and short the 5v to ground it could cause this problem. unplug sensors (cam throttle and something else?) also check voltage between 5v and ground on one of the sensors plugs. I was told not to load test this line. note that the 5v on the diagnostic port is a diff power rail per the forms.
SKIM Module:
Some people report corrosion in the skim module, check for corrosion on the SKIM module connectors. You can also open up the SKIM module and check for corrosion / broken antenna joints, bad capacitors etc.. note that you have to desolder the antenna wires to get the board out.
SKIM Module power and ground:
using a 12v bulb across the 12v constant and ground wire if it lights up and stays lit its good. do the same for he 12v key power.
Pink = 12v constant
Black = ground
Blue = 12v key on
Yellow + purple stripe = PCI bus (all the pci bus wires are yellow & purple in this Jeep)
PCI bus continuity test:
use a volt meeter and some wire to test the continuity between the PCI bus pin on the computer plug to the SKIM module plug. Also check if the PCI bus line has either continuity to 12v or ground.
PCI bus diagnostic cap:
remove the PCI bus diagnostic cap if the Jeep works then one of the auxiliary PCI bus modules may bad / shorted/ bad wiring.
Scope PCI bus:
If you have an oscilloscope put it on the PCI bus and see if it looks normal. you should see 0V then discreet jumps to between 5-12v then back to zero.
PCM Repair:
There are several youtube video's showing how to open up the PCM and make repairs. the simplest seems to be to repair / re solder the connections for the 5v power supply and the 5v power supply is relatively easy to get to compared to the computer itself. Repairing the solder joints on the pins of the PCM itself appears to be much more involved and require cooking the board out of the potting material that seals both the board from weather and to the case. I've not tried either of these.
Ground Wires:
Ground wire corrosion can cause just about any electrical gremlin out there in a car, several forms have people reporting that methodically cleaning all the grounds in the vehicle fixed issues similar to this one... I did not go down this route.
Useful Links:
www.jeepforum.com/threads/2001-jeep-grand-cherokee-4-0-no-gauges.4436301/
allcomputerresources.com
note that according to their site a SKIM delete does NOT include any diagnostics, so if you send them a bad computer they will delete the SKIM function and send you your same bad computer back. This is why I chose to just buy a new computer and delete the skim. I figured its most likely the PCM but could still be the SKIM and a new / refurbished computer with the SKIM delete would take care of both. ~ 300. for my computer they did not require a core, but they do on some. I put my order in over the phone (required VIN )
#Jeepstalls
#keylight
#SKIM

Пікірлер: 32

  • @andrewm5566
    @andrewm55667 ай бұрын

    I had the same problem. Cleaned the grounds, tried leaving battery disconnected at night (helped a bit) but the fix was to spray lots of electrical cleaner on the connections to the ECM, been good ever since

  • @WhisperingWildMarketFarm

    @WhisperingWildMarketFarm

    7 ай бұрын

    That’s awesome!! Glad yours was an economical repair. Thanks for adding your solution to the comments!!

  • @Mo_Money73
    @Mo_Money73 Жыл бұрын

    Man thank you for making this video. I bought a jeep and it started having this exact problem and I’ve struggled to find anything similar. I’ve tried everything I almost sold the jeep after this ima have to give it a shot.

  • @WhisperingWildMarketFarm

    @WhisperingWildMarketFarm

    Жыл бұрын

    Your welcome! I hope it’s useful and wish you the best of luck on fixing yours.

  • @TimMoney

    @TimMoney

    11 ай бұрын

    Just sent ECM to all computer resources removed skim. Now it starts even when key light son. But still experiencing random shutdown while driving

  • @CaptainMorgan68OU1

    @CaptainMorgan68OU1

    10 ай бұрын

    Did the computer fix yours having same issues just bought it doing exactly same thing watched this and did as you did if it did fix it where's best place to get one

  • @Ophidicus
    @Ophidicus5 ай бұрын

    I had this exact problem last year, it was the ground under the center console near the ABS Module, I had swapped out the heater core a few years prior and must have left one of the ground screws hand tight. I tightened it up and got my gauges back and the engine stays running because the immobilizer is grounded

  • @WhisperingWildMarketFarm

    @WhisperingWildMarketFarm

    5 ай бұрын

    Interesting! Thank you for posting

  • @tv10morehead
    @tv10morehead Жыл бұрын

    IF it cranks without starting on some models it could be the 10amp PCM/ECM fuse under the hood has a hairline break that is hard to see, can happen if you jump a dead battery, so swap that fuse it is labeled on the lid which one it is . ALSO if like me you get a spare dumb key for the door and you put it in to start the Jeep, it does the same thing if you or the wife uses the wrong key. & The Keyfob even works to lock and unlock doors but it acts like the keys were 'deleted', after 1999 the error code Pxxxx comes up for the skim communication, but it still can just be that 10amp little red fuse by the battery, since he does not mention it , check that first with a bright light or just swap it. & I'm rootin for you hope that's it.

  • @WhisperingWildMarketFarm

    @WhisperingWildMarketFarm

    Жыл бұрын

    Good To know! Thank you for adding the info!

  • @user-ou2ws2lw7c

    @user-ou2ws2lw7c

    Жыл бұрын

    Thanks alot u save me a lot of time nd money❤.

  • @Paintgirl74

    @Paintgirl74

    Жыл бұрын

    My 99 v8 is doing the SAME thing happens when it’s get wet?! They pulled horn fuse out why??? Shows a p1698 too! I am going to check fuses

  • @WhisperingWildMarketFarm

    @WhisperingWildMarketFarm

    Жыл бұрын

    @@Paintgirl74, This seems like it would be very frustrating to find. Wet could be water / condensation getting someplace it dose not belong shorting out something or the cooler temps opening up bad solder joints. If this is a Jeep with a distributor I would strongly suspect the cap and say try replacing that. Google says Jeep started moving away from distributors in 99 so may have one. Checking / cleaning ground connections is a good place to start. Not sure about the horn fuse. A quick google search shows a few people getting that code but their trucks still running so that suggests it may be more of a bus issue like when it’s wet things can’t talk. From what I read any device on the buss going faulty can mess with the bus / cause communication problems. There is a connector under the steering wheel of some Jeeps that when pulled can disconnect portions of the buss In my Jeep the truck would still start but things like door locks and displays stoped working if you pull that when it’s not working and it starts then you know the problem is with one of the peripheral devices. If it still dose t work then putting a scope on the bus to see if the voltage stuck high low or noisy may help. Otherwise it is disconnect devices like the tcm/bcm/pcm/ecm until the fault condition goes away. If the fault condition does not go away when the devices are unplugged then it may be wiring . If there is no issue when scoped try re seating the bcm ecm/pcm and tcm connections. If it’s still not working after that I’d start suspecting a bad solder joint on the tcm or pcm/ecm. Else this could all be a red herring and you just have a bad coil pack that dose not like cold / wet conditions. Thats about all I’ve got for speculation on this issue. I hope your able to get this solved.

  • @markgabello58
    @markgabello587 ай бұрын

    Yeah, that's systematic. I didn't turn alarm systems skim card. Something's wrong with the alarm system computer won't let the vehicle start

  • @mechsupernova
    @mechsupernova5 ай бұрын

    When I went to start mine earlier it clunked, all the interiors lights went off, all the gauges went out, then all the hands started doing a self test everytime I tried to crank, none of the battery terminals where loose so I removed the positive went and turned the key a few times and put it back and everything was good, never seen it so this before and i can't find anything online about it

  • @WhisperingWildMarketFarm

    @WhisperingWildMarketFarm

    5 ай бұрын

    Hum. This sounds like there may have been an issue with a connection. I find removing the battery cables cleaning both the battery and the cable clamp then re connecting them usually fixes this. Often there is a good enough connection that low amounts of power can flow but once a high draw like the starter kicks in there’s to much resistance and the voltage drops or disappears causing everything to go dark. Thank you for posting your experience!

  • @domstarkey7279
    @domstarkey7279 Жыл бұрын

    I fixed my door wire I jus learned if you turn your key to assessor 3 times an then it work granddaughter told me it happen to her a time or to

  • @WhisperingWildMarketFarm

    @WhisperingWildMarketFarm

    Жыл бұрын

    It seems to be a common problem with these Jeeps wires just seem a bit to short.

  • @omarnaji1467
    @omarnaji14677 ай бұрын

    ‏كيف تصنع ولداً متعبا، وكيف تصنع ولداً منضبط السلوك ؟ ‏ ‏معادلة تربوية: ‏نقد جارح + تسلط = شخصية مدمرة ‏ ‏معادلة تربوية: ‏مقارنة سلبية + تحقير = هدم شخصية ‏معادلة تربوية: ‏حماية زائدة + عدم تحميل للمسؤولية = إتكالية ‏ ‏معادلة تربوية: ‏احترام + مدح = ثقة عالية بالنفس ‏ ‌‏معادلة تربوية: ‏تجاهل للسلوك السلبي + تركيز على السلوك الإيجابي = تعديل سلوك ‏ ‏معادلة تربوية: ‏تكليف الابن بمسؤولية + مساندته عند الحاجة = شخصية رجولية ‏معادلة تربوية: ‏إعطاء ثقة + غرس قيمة الصدق = رقابة ذاتية تستحق الحفظ في ذاكرة كل أب وأم ومعلم ومعلمة 🌹شهادة الدكتوراه والماجستير ستصبح هباءاً منثورا في أول ليلة في القبر و يبقى درس الصف الأول الإبتدائي من ربّك من نبيّك ما دينك..

  • @PabloLowondoski
    @PabloLowondoskiАй бұрын

    The electrical in the driver door ,ehat would prevent it grom starting,,?

  • @WhisperingWildMarketFarm

    @WhisperingWildMarketFarm

    Ай бұрын

    Potentially. The door locks and window regulators are controlled by a computer that shares a communication bus(wires) with the other computers in the vehicle if the bus gets shorted it could block the other computers from being able to communicate.

  • @PabloLowondoski

    @PabloLowondoski

    Ай бұрын

    😊i think also the key fob or security system might be a reason and possibly a short in the relay box

  • @PabloLowondoski

    @PabloLowondoski

    Ай бұрын

    😊i think also the key fob or security system might be a reason and possibly a short in the relay box

  • @PabloLowondoski

    @PabloLowondoski

    Ай бұрын

    😊i think also the key fob or security system might be a reason and possibly a short in the relay box

  • @deezotat2man349
    @deezotat2man349 Жыл бұрын

    Did it work I have same issue

  • @WhisperingWildMarketFarm

    @WhisperingWildMarketFarm

    Жыл бұрын

    Yes see the follow up video How To: Jeep computer replacement SKIM removal kzread.info/dash/bejne/goRh0ciIp9y4fsY.html I suspect that it was the solder joints on the main computer. So I replaced the computer.

  • @davidessien5465
    @davidessien546511 ай бұрын

    How can I fix this car problem? It's a 2005 CHRYSLER 300 3.5L V6 2WD AUTOMATIC 150,127 MILES The car listed above is limited and according to the client had a horn issue so was taken to a garage. Although the horn later worked, a more complex issue happened to the car. A no crank no start and also a crank no start, whenever security light came up it doesn't start or start and stalls immediately. Infact, ECM was replaced by the engineers but that didn't fix the issues. I finally fixed all these issues listed above with both new and an old ECM. kzread.info/dash/bejne/oHp1l8uBqNq-j8Y.htmlsi=rSRKrmfj4ywRXIQX. That's a brief video of what I'm trying to explain. When I was about to go, the client pleaded for me to help him fix these issues below, such as, ABS, airbag, traction control light; hard starting,single turn signal for both sides doesn't work but hazard light blinks normally when the switch is turned on, wipers doesn't work too. Mostly for the trafficator / turn signal that wasn't functioning, what could make it to be inoperative and, how can I fix the problem in that car? Can you guide me please, on the repair procedure to fix the problem? This were the codes I got below drive.google.com/file/d/1nZQtpE8DuGGQoeA4Lc9Iob-BBbRfzs0H/view?usp=drivesdk Does it require a TIPM or trafficator switch replacement? Please, how can I carry out a test to verify if it's TIPM or a trafficator switch that is faulty? www.startmycar.com/chrysler/300/info/fusebox/2005#anchorfusebox1. That's the fuse box diagram I saw online In addition, when testing the fuses at the trunk I noticed that not all the fuses were available, some were empty. Thus, I decided to swap fuse 4 that was available to 5 that was empty. As I did, I noticed an immediate electric spark just by the fuse touching the empty terminal meant for fuse 5. drive.google.com/file/d/1qqOKGWB08fWkArDwwx9hQ8QLU0zU5Ang/view?usp=drivesdk. That's the link to what I'm trying to explain. I tried that again with a known good fuse into that location and noticed another spark/ spike. why is it sparking whenever I attempt to put a fuse in that location? I compare that fuse location where there was spark to another good working 2005 Chrysler 300 and saw that there was a fuse in that location. Could that also be responsible for the cars turn signal and wipers problem? How do I address this sparking problem in that fuse location? When I finally succeeded to start the car, as a result of checking the turn signal switch and wiper at under the dashboard using my testlight connected to batt + (pin 16) of obd2 connector and activating the hazard light, when I touched a particular blue/white twisted wire the hazard light seemed it wanted to stop it seem like something is wrong there, when I touched the blue/white wire again the car problems reoccurred all over again. Security light remains ON, lightning bolt light, etc came back on and car didn't idle if it even struggle to start and sometimes doesn't start at all. Fortunately, I was able to start the car again. But the no turn signal, no wipers still remained, how should I fix these ones?

  • @WhisperingWildMarketFarm

    @WhisperingWildMarketFarm

    10 ай бұрын

    Hi David, That sounds like quite the perplexing problem and it sounds like you have been able to fine quite a bit of information around it. I’ve no experience with those cars myself so I can only offer some basic advice. Check grounds.I can’t tell you how many weird and unexplainable electrical issues have been resolved by locating and cleaning up ground connections. Look for damaged wires. Many of these systems use a shared buss(wires) for communication so damaged wiring in an unrelated spot can sometimes cause other systems to malfunction. Where wires go from the body of the car to doors is a common spot. You may also want to check for corrosion on junction points (typically around the firewall or in the dash). Rodents tend to like to nest in or around fuse boxes and chew wires. Aside from that if you think it’s a buss issue which it kinda sounds like you suspect then you could try disconnecting the other devices on the bus. I hope that helps and good luck.

  • @omarnaji1467
    @omarnaji14677 ай бұрын

    عن إبراهيم ابن أدهم، قال: كان يقال ليس شيء أشد على إبليس من العالم الحليم، إن تكلم تكلم بعلم، وإن سكت سكت بحلم. القسم: فوائد من كتاب الزهد الجزء الرابع

  • @user-ke1yu9nf2n
    @user-ke1yu9nf2n Жыл бұрын

    Digalo

  • @WhisperingWildMarketFarm

    @WhisperingWildMarketFarm

    Жыл бұрын

    Hola Pedro, lo ciento mi espanol no es bueno. Me habla espanol con una picano nino.. es muy muy mal.