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Discussion Starter · #1 ·
I need to check every ground on this truck. Can anyone tell me where ALL of the grounds are located. I'm still blowing the #7 "meter" fuse. The code was vehicle speed sensor circuit low..after installing a new speed sensor, I'm still blowing the meter fuse. Thanks
 

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The speed sensor code was set because the fuse that provides power to the speedometer and the vehicle speed sensor (CB7) was blown. That is not necessarily the cause of the problem, it is the symptom. CB7 also supplies the brake light indicator, the ABS indicator, the low fuel indicator and a voltage regulator that provides power to the fuel gage and fuel tank sender and coolant temp gage. The fuse is blowing because there is a low resistance path to ground on this circuit. The most probable cause of this is a shorted fuel/coolant gage voltage regulator. You don't need to know the ground points to troubleshoot this problem. You need to find the low resistance path to ground.
 

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Discussion Starter · #3 ·
Thanks Buster28...is this voltage regulator easily accessible and can I replace it...I swear I'm about to burn this car!!! J/K...I would like to conquer this beast!

Have any comments on this reply? As it doesn't mention the items you pointed out being on the circuit. I have a schematic which agrees with Anomalous reply...just looking for all opinions and thank you...

Anomalous said:
I just had this problem with my 97 Rodeo a couple days ago.

In my case, the cause turned out to be that the 12V supply wire for the VSS had worn through and was shorting out. The VSS supply is on the same fuse as the instrument cluster.

The VSS +12V wire runs out to a spot just behind the driver side headlight, back under the engine, up over the transmission, and finally connects to the VSS on the back of the transmission. Where the wire turns to go up to the top of the transmission, it goes behind a metal plate that looks like it may be there to shield the wires from the hot exhaust pipe. The edge of the metal plate had worn through the protective plasting tubing around the wire bundle, and then through the +12V VSS supply wire.

I don't know how common this issue is, but it might be worth checking since the symptom is the same as I saw.

In case that's not the problem, it may be helpful to know that fuse CB-7 supplies 5 different systems: vehicle speed sensor, seat belt key and light reminder buzzer, meter assembly, rear defogger relay, and shift lock controller.
 

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Discussion Starter · #5 ·
Well...when the instrument cluster was working all gauges were functioning normally. The only thing that works now is the airbag test indicator and the lights that show which gear your in...the rest of the instrument cluster is out...I have changed both VSS and put in a new (85K cluster from ebay). I have disabled the rear defogger system pulling the fuses and the relay. The seat belt buzzer, lights reminder buzzer, and shift lock are all working normally, which seems odd since they are on the #7 fuse and it blows instantly. I've tested every ground I can find and they are good with zero ohms on a test meter. The alternator is putting out 14 volts and I cant find any bare wires anywhere. I'm lost....

I just thought of another thing...the radio likes to cut in and out, and when it does the cassette player starts fast forwarding and making clicking noises. I never associated the two problems, but thought I'd point it out. I have pulled the stereo and disconnected and reconnected it without curing the problem
 

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If the seat belt buzzer, lights reminder buzzer, and shift lock are all working normally they cannot be on the #7 fuse circuit. If you have a schematic that indicates they are on that circuit it has to be wrong. You need to make a listing of every thing that does not work with fuse #7 blown. Also make sure there is no aftermarket electrical devices connected to the fuse #7 circuit. Post your results.
 

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Discussion Starter · #7 ·
Buster28 said:
If the seat belt buzzer, lights reminder buzzer, and shift lock are all working normally they cannot be on the #7 fuse circuit. If you have a schematic that indicates they are on that circuit it has to be wrong.
I agree...I was provided some scans from a 96 repair manual, supposedly the same as 97.

But those items can't be on that circuit because they working. No aftermarket stuff on the car. The only thing I can tell ids not working is the instrument cluster and the rear defogger system (if it is on that circuit)

Would there be any problem with just running a new 12 volt supply and ground to the #7 meter fuse?
 

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z21ranger said:
Buster28 said:
If the seat belt buzzer, lights reminder buzzer, and shift lock are all working normally they cannot be on the #7 fuse circuit. If you have a schematic that indicates they are on that circuit it has to be wrong.
I agree...I was provided some scans from a 96 repair manual, supposedly the same as 97.

But those items can't be on that circuit because they working. No aftermarket stuff on the car. The only thing I can tell ids not working is the instrument cluster and the rear defogger system (if it is on that circuit)

Would there be any problem with just running a new 12 volt supply and ground to the #7 meter fuse?
I wouldnt you need to find out what is shorted out.
 

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Start trouble shooting by disconnecting the the instrument cluster and inserting a new fuse. I am reasonably certain the rear defogger problem is not related to the fuse #7 problem.
 

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z21ranger said:
Bansil said:
I wouldnt you need to find out what is shorted out.
I've been trying...I've ran wal mart out of 15 amp fuses more than once. I'm about out of ideas..
I had same problem with my turn signals last week(see my post) I had to break down every posiible connection and go from there.
I will look and see if I have a 97 manual
Did you ref. an Isuzu manual or a POS aftermarket one.
It is a pain but worth it in the end,dont give up yet.

Keep feeding us info
 

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I do not have a 97 manual all others 94,95,96 ref multiple systems including combo switch (turn signals) dependant on year.
#7 does cover buzzer vss and interlock on all.
In 95.5 when they went obdII it could of changed.
You do not have a problem with the vehicle grounds,if you did stuff just wouldn't work because they have no ground.
Your problem is a "dead" short to ground somewhere between the fuse box(non 12 side of fuse)and the end of wires that make the correct ground.
So 1st thing we need is a pdf off wire diagram.
I would edit post to say something like....."need wire diagram,97 rodeo " then discribe in your first post (above) that you need a diagram of fusebox and #7 fuse and its systems.
 

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Discussion Starter · #13 ·
first...thanks everyone for all the help..really appreciated.

I was given the schematics I have now by a forum member, it was for a 96 but he was pretty sure the 97 was the same.

I have tried a fuse with the instrument cluster completely removed and it still blew.

I'm really starting to suspect something in the rear defogger. It doesn't work. I don't get the power light in the switch on the dash. The elements have peeled off the rear glass and the first time the cluster went out, I had a piece of the element hanging down off the rear glass, so I trimed it off and the cluster worked and no blowing the fuse...I went and had the truck tinted and of course they worked on the rear glass and it started blowing the fuse again and has ever since.

I know the components of the rear defogger are the switch, relay, and the wiring. Is there an actual defogger part that I'm not seeing? Something back around the rear glass?
 

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you could always unplug the relay, that should stop the power going back to the "grids"
if it blows a fuse then you have eliminated from relay back
 

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Troubleshooting electronic/electrical problems is a process of elimination. Each time you test something you get another data point and eventually you solve the problem. The fact it blew the fuse with the cluster removed tells you a lot, because there is a lot of stuff on the cluster that is powered by fuse #7 which you have now eliminated. Next step is to remove the Turn/Hazard Flasher to be sure it is not the problem.
 

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z21ranger said:
Thanks buster28...would that be something to check even if signals and flashers are working fine? Any idea where that flasher is?
They are?with a blown #7.....
ok I'm confused we def. need a 97 wire diagram to fix this issue.

What doesnt work on the truck with blown fuse?
Be specific
 

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Discussion Starter · #20 ·
I agree with the wiring diagram need! I've been all over the web and cant seem to find the right one for a 97.

As far as I can tell..The cluster (speedo,tach, oil p, coolant temp, gas gauge,
volts) all out. The rear defogger is out, but I've puled the relay and pulled the connection from the dash switch.

BEFORE this issue with the # 7 fuse..the power/winter switches were/are out with no indication in the switch or on the instrument cluster lights....

something else is obviously on this circuit that I haven't figured out yet.

I'm going looking for a haynes manual this afternoon....

Thanks again for all the brain scratching on this thing! :thumbup:

Its a shame I cant figure this thing out...she's a clean little old ride!
 
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