QuestionHi. Thanks for the quick answer and help. I have briefly spoken to the dealer and they proposed to replace the complete wire harness which would cost about 2500 bucks. They said this would be better because it is difficult to allocate the short. Do you know if there is any preferred location where the wire tends to get a short? Is the wire harness known as a common problem of the XG? I am at the moment a little bit uncertain if I should have the dealer invest the time in searching for the short or to have the wire harness replaced right away. Thanks again for your help. Alex
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Thanks for the answer. It is fuse #23 which always blows up.
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I have a Hyundai XG300 built 1999 and problems with my transmission. At first the transmission rarely started to shift very harsh into the 3rd gear and got stuck in fail-safe mode. I took it to the dealer and they replaced the gear sensor. After that the car worked fine for a couple of weeks. Then all of a sudden the speedometer quit working and the dealer replaced the input speed sensor. It worked for a few days and the speedometer died again. After that I figured that the fuse for the input speed sensor blew up. I replaced the fuse and the car including the speedometer works fine again. However, typically only for a few miles before the fuse blows up again. As soon as the fuse blows up the speedometer and the light indicating the transmission mode (P,R,D,N) stops working, but the cars still shifts (sometimes a little bit odd). When I then turn off the car it only will start the gear in fail-safe modus until I replace the fuse again. What could be the problem? Thanks Alex
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It's likely there's a short circuit somewhere causing the fuse to blow. There isn't any fuse for the speed sensor itself. If you can tell me which fuse box the fuse is located in (underhood or interior) and the label on the fuse box cover corresponding to that fuse, I can look at the schematic and try to make suggestions as to where the short might be.
If you'd like to look at the schematics yourself, you can see them at www.hmaservice.com. You'll need to register for a free account, and the site requires Internet Explorer. You'll probably also need Adobe SVG Viewer (free download) to view the schematics.
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I'm sorry, Alex. The fuse is indeed for the vehicle speed sensor (as well as the transmission range switch). I had originally thought you were talking about the input/output speed sensors which don't have a separate fuse for their power.
From the interior fuse box, the wiring from fuse #23 goes to the underhood fuse box. From there, it switches to the control harness and goes to the transmission range switch and the vehicle speed sensor.
You should first check the wiring to see of you can find anywhere it has rubbed through on a metal part of the car. If this happens, it'll cause a short and the fuse to blow.
The problem could be anywhere in the wiring between the inside fuse box and the sensor and range switch, in the range switch itself, or in the underhood fuse box. I'll take the fact that the vehicle speed sensor was replaced without resolving the issue as evidence that the vehicle speed sensor is not the issue.
AnswerThere are a few problems with just replacing the harness.
First, it assumes the problem isn't in the range switch, underhood fuse box or transmission computer. Although these items rarely have short circuits that blow fuses, it's theoretically possible.
More importantly, I failed to notice when I originally looked at the schematics that the power from fuse 23 flows through the range switch to switches on the shifter, to the cluster, and to the IMS (if equipped). The area by the shifter should be one of the primary areas to be inspected, since it's a location where things moved. It's possible there is a pinched wire there that causes the fuse to blow only when the gearshift is in a certain position.
Yet another issue is that there are two wiring harnesses involved: the main dash harness and the control harness.
Hopefully, you're getting the picture that I'm sending you away from replacing the harness. If you're to spend $2500 on a repair, the shop should be able to be sure it'll fix the problem. And they won't be able to do that without some diagnosis. Furthermore, the fact that they've recommended one of the two harnesses involved and don't seem to have eliminated all the other possible causes leads me to believe that whomever is checking your car may not have sufficient knowledge or skill to do this type of diagnosis.
Since the fuse won't blow at will, diagnosis will require some tactics to narrow the areas where the problem may lie. From fuse 23, a wire goes to the underhood fuse box. Then two wires exit the fuse box: one going to the vehicle speed sensor and the other to the range switch. I'd recommend first determining which branch of the circuit the problem was in. To do this, there'll need to be some modifications to the wiring. On the bottom of the fuse box, where the two wires exit, cut the two wires and install a 10A fuse in line with each of the wires. Then replace fuse #23 with a 15A fuse.
Depending on which fuse blows, you'll learn something about the location of the short. If the 15A fuse blows, you'll know that the problem is between the two fuse boxes or in the underhood fuse box. If one of the 10A fuses blows, you'll know that the problem is in the circuit branch controlled by that fuse.
If you can read the schematics, I encourage you to register for a free account at www.hmaservice.com and attempt to follow the logic above. The site requires Internet Explorer, and you'll probably need Adobe SVG Viewer to view the schematics.
