'00 XJ Cherokee 4.0 AT
I’m currently having mixed feelings about my Jeep. One day I want to torch it, the next I’m buying accessories for it and treating it to a full valet.
The troubles began a couple of months ago. I was so gatvol with my Cherokee’s drivetrain noises that I decided to do something about it. My solution was simple: install a kickass sound system to drown out the Jeep’s creaks, croaks and rattles. So I splashed out and bought two sets of 5” speakers, an amplifier and an 8” subwoofer. I was halfway through the installation when I realised I needed more cabling. I jumped into the driver’s seat and turned the key – the engine spun over but failed to fire up. I looked at my new speakers and thought: “What the hell is in these things – they’ve poisoned my Jeep!” I eventually came to my senses and turned my attention to the more logical explanation – and the closest person to blame – my two-year old son. While I was installing the speakers he’d kept himself busy by playing with the ignition switch, probably burning out the coil pack. That was my initial diagnosis
– I’m not particularly proud of it now, but I was on a witch hunt and would’ve blamed the postman if he was nearby.
My Jeep stood in my garage for 21 days. Three loooooong weeks of prodding, probing, engine cranking, and swearing passed. I stared at it for hours on end. I drowned my sorrows in drink. I refused to take the Jeep to a mechanic, because I couldn’t afford to. Remember my new kickass sound system? During those 21 days I’d performed numerous diagnostic tests, checking the Jeep’s fuses and relays and making sure that the three vital ingredients were present: air, fuel, spark. As it turned out, the last mentioned was missing. My research revealed that there are three common scenarios which can cause this engine’s ignition system to fail: a faulty ignition rail, a dysfunctional Crank Shaft Position Sensor (CKP) or a burnt-out Powertrain Control Module (ECU). As you can imagine, none of these problems have a happy financial ending.
Hoping for the lesser of three evils, I was rooting for a malfunctioning CKP; they’re not too expensive (about R1 300) and are relatively easy to install. What’s more, I was told by numerous folks in the field that this is a common problem with these Jeeps – nine times out of 10 it’s gonna be the CKP. After purchasing a new unit from HB Willies (021 557 7225) I flew back home, dived under the Jeep, whipped off the old CKP and bolted down the new one. With the prospect of success so near, I could barely contain my excitement and nearly dropped a bolt into the transmission bell housing. Once the new CKP was in place I shot into the driver’s seat and I turned the key. Nothing, nadda, niks. In fact, to add insult to injury, now the starter motor wasn’t even working! The only sounds coming from the Jeep were the click of the ignition switch and the dull thud my head made as I banged it against the steering wheel.
The fact that the engine had gone from swinging over to doing absolutely bugger all made me think that the alarm / immobiliser was to blame. Maybe after my numerous attempts to start the engine the immobiliser had completely shut down to prevent any further starting attempts. I’ve heard of this happening, and when it does you need to reprogramme the vehicle’s computer so that it recognises the key fob again. But in order to reprogramme the immobiliser you fi rst need the SKIM code, which is kept by the manufacturer. I pulled some strings and managed to get my vehicle’s code. I then contacted a reputable locksmith and asked them to come to my house and reprogramme the Jeep’s immobiliser. Unfortunately, the locksmith’s programming device couldn’t communicate with the Jeep’s onboard computer. Yip, that’s right, my XJ was brain dead.
After a few short breaths into a paper bag I locked the garage door, handed the keys to my wife and gave her the following instructions: “Hide these from me and don’t let me go into that garage for the next five days. I can’t be around that vehicle anymore.” After about a week or so I gave Mike Holleis a call. Mike runs a Jeep repair shop in JHB and knows the XJ well. He also owns one. But because I’d already performed most of the common diagnostic tests myself, there was little Mike could do to help me without examining the vehicle himself. I’d hit a dead end.
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