as i stated before, my guage fuse keeps popping. i'm putting a new fuse in like every other day. but i think i found the prob thoough. i noticed that everytime it pops, it's when i floor it to go from a stop to like fast. like a yeild on a highway or something. anyway, everytime i change the fuse without turning the car off, my INFL REST light is on then, which i'm assuming is my airbag light. oh, the car is a 91 rs 305 so you know. what i was thinking was the jerk that the car does when i floor it causes something with the airbag sensor or something, and i blow my fuse. what can i do? is there a way to test something, or should i just disconnect the airbag sensor. where would that be anyway? what should i do? i'm almost positive that it has something to do with this INFL REST thing. thank you.

 

I'm not sure that the SIR (air bag system) is the cause of the gauge fuse blowing.

When exactly does the inflatable restraint indicator illuminate after changing the fuse? Of course it's supposed to light when first starting the car (standard gauge light check), but thereafter, all the lights are supposed to be out unless there is a fault.

When you change the fuse, is this light "on" continuously? Is this why you said "...everytime i change the fuse without turning the car off..."? If so, you probably have a bad SIR (wiring, module or modules).

Does this light (air bag) come on while driving? If so, you probably have a bad DERM (Diagnostic Energy Reserve Module) or the wiring going to it.

I would see if the SIR (Supplemental Inflatable Restraint) system has anything to do with your gauge fuse blowing.

1. I'd remove the SIR fuse to remove power and see if the gauge fuse still blows. If not, then something in the SIR is causing it to blow (as stated above, the wiring or module(s)).

2. You could also remove the DERM (essentially the "brain" of the SIR) located under the dash, below the windshield, on the passenger side. You'd have to remove the instrument panel pad and then cut off an unused mounting screw tab from the front edge of the instrument panel, just above the DERM module to gain access to the DERM. Then remove the connectors. With this disconnected, does the fuse still blow?

I notice that the DERM is connected to the gauge fuse (+12), labled "SIR Incicator High". Note that this is not the connection to the air bag light. This is a point that gets +12 directly from the gauge fuse. Perhaps the DERM is drawing too much current from this connection (due to a bad DERM) causing the fuse to blow. This is a pink/black wire connected to B9 on the DERM.

The gauge fuse (according to my 91 service manual) is connected to the following points:

1. DERM (Diagnostic Energy Reserve Module)
2. Daytime running lights module (if you have it)
3. Multi-function lever (cruse control)
4. Brake switch (not the brake pedal switch)
5. Instrument cluster indicators and gauges
6. Convenience center audio alarm assy (key in ignition/lights on/etc. alarm)
7. Defogger control
8. VSS (Vehicle Speed Sendor) buffer
9. A/C compressor control relay (V6 and VIN "T" only)
10. Canister purge solenoid valve (V6 and VIN "T" only)
11. Air select valve (V6 and VIN "T" only)
12. Air diverter valve (except V6 and VIN "T")
13. Exhaust gas recirculation (EGR) solenoid and assembly. (except V6 and VIN "T")

Make sure you're using a 10 gauge fuse when replacing it

Since the fuse does not blow immediately, then it sounds like the problem is intermittant or something is drawing too much current, but not quite enough to blow the fuse. Given enough time though, the fuse will eventually blow (fuses blow due to overheating from the resultant overcurrent).

First check to see if all of the above devices are operating properly. You may also want to see if you can see anything obvious, such as a loose wire shorting to ground somewhere. Otherwise, it looks like you'll going to have fun troubleshooting the above items one by one.

All of the above is referenced to my service manual - not personal experience removing the DERM.

[This message has been edited by Stuart Moss (edited June 16, 2001).]

 

This sounds like the same type of problem that I encountered with my 87 gta.
The same fuse pops and has done so with increasing frequency. Same acceleration symptom as well. I've tried a variety of options but no luck yet. Probably over looked something. My car sets a code 24 indicating a vss buffer problem; it also implicates a possible computer problem.
And now the car fires but no run and no fuel pump sound. this is after a swapped in a rebuilt ecm with the same result. Getting ready for a big block crate and hefty carburetor!