1999 Rodeo Horn stuck - SRS module, how dangerous?

03-27-2010, 06:35 PM
My horn is stuck on. I'm certain it's something concerning the horn switch since the first few times it got stuck briefly, I was able to stop it by tapping on the switch.

I was accessing it just now to see if I could repair the switch contact, or if I'd need to replace it.

Removing the SRS (air-bag) assembly was easy enough (2 torx tips fasteners), but once I had it out I could see that the horn switch wasn't accessible unless I could get the cover off.

I'm hesitant to take the SRS assembly apart for obvious reasons. The cover doesn't seem to want to come off easily except at the sides.

Just how dangerous is it to remove the cover, and how much prying does it take?

Is it possible to remove the cover with the SRS in place?

Thanks for any assistance. As for any repair, once I've completed it I will submit a full report.

Huntington Beach, Ca.

03-30-2010, 01:28 AM
Lots of views, but no replies. I called many dealers today, including St. Charles Isuzu, and found that none of them sell the horn switch.

They all sell the entire air-bag assembly only, and the same goes of course for auto-parts stores. The air-bag assembly sells for $550.00 plus tax.

I did read a post from another location that was sent to me by a co-worker where a person described how they disassembled the air bag assembly and tinkered with and fixed the horn switch.

I'm not planning to go that route. Fixing the horn just isn't worth that risk to me. I'm going to get a heavy-duty momentary switch that I'll mount myself.

I'm also going to disconnect the current failed switch so that when I reinstall the fuse, at least I'll have my alarm back. Many say that the horn and the alarm use different "horns", but I don't think that's true, since right now I don't get any chirping when locking or unlocking the doors with the remote.

Of course I'm also going to check ebay, Craigslist etc... for the complete assembly.

03-30-2010, 08:47 PM
This is a rare rare problem. There was a post a couple weeks ago with an owner with the same issue. I've been reading Isuzu forums for 11 years now and have only seen this issue a couple of times (no clue as to fix).

If you think it is the part you described, check out www.car-part.com to find a local pick and pull (junk yard) near you and find the part there....

best of luck!

03-31-2010, 10:04 PM
Hey Ryan,

Thanks for the input. I found a replacement driver's-side airbag on ebay for $50 plus $30 for S&H in a special haz-mat container, and the seller guarantees me that the horn switch is in good working order.

I was going to mount another switch to operate the horn with rather than pay $550 for a new airbag, but replacing it this way is much better.

I should have it in a few days. I disconnected the 12V horn wire and tied it off beneath the air bag so that my alarm would work again. Putting the horn fuse back in also gets me back to where my code reader works, since the same line is used to supply 12V to the OBDII connector.

I do have a question about the EGR valve though. I've been hearing some clicking when I get up to 45mph but it cuts out at around 50mph, and it isn't based on engine speed/rpms.

It seems to me that it's coming from the exact area where the EGR valve is, though you have to listen hard to ever hear it. A few times I've had my CEL come on and the codes I read had to do with the EGR solenoid valve.

I'm almost certain that it's the EGR valve making the noise, but I don't know if the solenoid's just getting weak, or if it's the input to the valve that's cycling it on and off. I've reset the CEL a few times and it came on after a week or so. At the moment it's been off for a few days and a few hundred miles.

I'm thinking of just replacing it, but it seems to me that with solenoids being mainly just a coil and a plunger, they usually are either good or bad, though I'm on the verge of 200K miles, so it's been cycled a ton of times.

Any experience with EGR valves? Seems to me that if I let this go too long it could start clogging up my catalytic convertors?

Any input appreciated.

Thanks Ryan

03-31-2010, 11:03 PM
I typically pull my EGR yearly and clean out the pintle with some carb cleaner.
Use a half can of cleaner. Spray some in, let it sit, push the pintle in and out. do this like 10 times and then bolt it back on to see if it helps.

EGR's do go bad but typically a good cleaning will fix them.

04-01-2010, 01:22 AM
Nice. I'm going to try that. I'll report back with what I find.

Thanks Ryan. You've helped me a lot over the years.

I always write procedures and report them back to the forum once I've performed a fix.

Thanks for your support. I'll let you know if cleaning the EGR valve works.

Huntington Beach, Ca.

04-01-2010, 01:25 AM
I'll also get back with info concerning the horn switch. It's due to arrive around April 6, but someone needs to be present to sign for it so it could be a few extra days.

I will report back on that and on the EGR valve.


04-05-2010, 12:11 AM
I cleaned out the EGR valve today, but to no avail. I still hear "something" clicking. a tapping, that sure sounds like it's coming from that area, but I can't tell since it isn't very loud, and it only happens between roughly 45 and 55 mph.

It always clicks at the same rate no matter the engine speed, so it isn't rpm related. I've had DTC 0401 a few times over the last month, and that's the code for "insufficient EGR flow". That code, coupled with the "clicking/tapping" made me think that it could possibly be the EGR valve.

The thing is, it seems to me that the EGR valve could be getting erroneous commands telling it to open and close repeatedly, which may be related to one of the other sensors; Map, MAF, throttle position, IAC, etc., and not a problem with the valve itself. I suppose the coil could be getting weak in the valve, or perhaps it's just worn out?

I just hate to pay $120 for the valve only to have the same issue.

This clicking doesn't seem to effect performance at all, but I don't want to let it go until it becomes a bigger issue for something downstream.

Any ideas? Have you ever heard of this symptom?

I did drive it for 20 miles after reinstalling the EGR valve, and right at the end of the trip I got the CEL and DTC 0401 again.

Let me know if you have some insight. If not, I may need to get it hooked up to a more sophisticated scan tool to narrow it down.


I also changed out the serpentine belt today. That was very simple and quick.

Any further input greatly appreciated. I should have the air-bag/horn switch assembly by Tuesday.

Cat Fuzz
04-05-2010, 11:50 AM
I'd go grab one or two from a self serve u-pull it type wrecking yard, clean it and install and see if the clicking goes away. This is a listing from Shucks website of all the vehicles our EGR valve fits. It's quite common. Usually, you can buy a part and if it doesn't work or fix your problem, you can simply return it to the yard for a refund. At least, that's how mine works.

1996 SLX

Buick back to top
2005 Lacrosse

2002 - 2005 Park Avenue
2002 - 2005 Lesabre

2002 - 2004 Regal
Cadillac back to top
2000 - 2005 Deville

2002 Escalade
2000 - 2002 Eldorado

2000 - 2004 Seville
1999 - 2000 Escalade

Chevrolet back to top
1993 Astro

2002 - 2005 Impala
1996 - 2002 Astro

1996 - 1999 K1500
2002 Avalanche 1500

1996 - 1999 K1500 Suburban
1996 - 2002 Blazer

1996 - 2000 K2500
1993 C1500

1996 - 1999 K2500 Suburban
1996 - 1999 C1500

1996 - 2000 K3500
1996 - 1999 C1500 Suburban

1996 - 1999 P30
1996 - 2000 C2500

1996 - 2002 S10
1996 - 1999 C2500 Suburban

1999 - 2002 Silverado 1500
1996 - 2000 C3500

2001 - 2002 Silverado 1500 HD
1996 - 1997 Express 1500

1999 - 2002 Silverado 2500
1999 - 2002 Express 1500

2001 - 2002 Silverado 2500 HD
1996 - 1997 Express 2500

2001 - 2002 Silverado 3500
1999 - 2003 Express 2500

2000 - 2002 Suburban 1500
1996 - 1997 Express 3500

2000 - 2002 Suburban 2500
1999 - 2003 Express 3500

1996 - 2002 Tahoe
GMC back to top
1993 C1500

1996 - 1999 P3500
1996 - 1999 C1500

1993 Safari
1996 - 1999 C1500 Suburban

1996 - 2002 Safari
1996 - 2000 C2500

1996 - 2002 Savana 1500
1996 - 1999 C2500 Suburban

1996 - 2003 Savana 2500
1996 - 2000 C3500

1996 - 1997 Savana 3500
1996 G3500

1999 - 2003 Savana 3500
1996 - 2001 Jimmy

1999 - 2002 Sierra 1500
1996 - 1999 K1500

2001 - 2002 Sierra 1500 HD
1996 - 1999 K1500 Suburban

1999 - 2002 Sierra 2500
1996 - 2000 K2500

2001 - 2002 Sierra 3500
1996 - 1999 K2500 Suburban

1996 - 2002 Sonoma
1996 - 2000 K3500

1996 - 2002 Yukon
Honda back to top
1996 - 2002 Passport

Isuzu back to top
1998 - 2000 Amigo

1996 - 2004 Rodeo
2002 - 2004 Axiom

1996 - 2002 Trooper
1998 - 2000 Hombre

1999 - 2001 Vehicross
Oldsmobile back to top
2001 - 2003 Aurora

1999 - 2002 Intrigue
1996 - 2001 Bravada

Pontiac back to top
2002 - 2005 Bonneville

2002 - 2005 Grand Prix

04-06-2010, 01:10 PM
Nice. I guess it makes sense to use a proven design across a wide range of vehicles.

I just found a used one on eBay for $25. I'm going to pop that one in and see if the clicking goes away. It's tough to tell exactly where it's coming from.

Good idea. Definitely a cheap troubleshooting alternative. I work long hours every day, so having it arrive in the mail works for me.

Thanks for your input. Very much appreciated. I'll re-post when it I get it. My airbag/horn-switch assembly is due to me today, and I'll post info on that fix as well.

04-06-2010, 05:23 PM
The airbag/horn-switch assembly arrived, is installed, and works great.

It's a really simple job, just 2 torx-tip fasteners holding it in. Just remember to disconnect the battery for at least 5 minutes before connecting or disconnecting the airbag so that it doesn't accidentally discharge (per the official Isuzu Workshop Manual).

I'm sure the airbag assembly can be disassembled and the horn switch can be messed with but from the write-ups I've read, it seems a very risky proposition, and definitely not worth the trouble since the switch itself seems to have many contact points down the length of it (or so it seemed from the description).

$550.00 plus tax new, but you can find them for around $50 on ebay. Just make sure that the person shipping it to you uses the correct "haz-mat" container approved for shipping airbags, since there's a fine for shipping "or receiving" one that's not properly packaged (seems strange to get fined for receiving one packaged incorrectly, but that's how the law reads). Mine came from Tom's Foreign Auto Parts in Waterbury, CT. It shipped to CA just fine.

I'll post again soon when I install the EGR valve I'm waiting for. Hopefully that will resolve my other issue. I'll post a full report.

04-19-2010, 10:07 PM
Replacing the EGR valve did NOT solve the issue of the "clicking" I hear between roughly 45 to 55 mph.

It's very possible that the EGR valve is making the clicking sound, but it could be that it's being signaled to energize and de-energize repeatedly by the ECM and/or due to faulty input from other sensors (MAF, IAC, MAP, Throttle body position etc....)

If I hold the valve in my hand and shake it vertically (gently) it does make a sound very similar to the clicking that I hear.

Lately I haven't had a CEL come on, so I'm not quite sure what I'll do next.

The clicking sound is very subtle, I have to have all of the windows fully up and the radio off to hear it, but when it's your car, you know when things change.

I don't really get any performance issue from this, other than an occasional wandering idle at a traffic light, or a stall after pulling off the freeway.

My guess is that some other sensor is feeding erroneous information to the ECM, or that the ECM itself is glitching, either one of those likely driving the valve to open and close repeatedly.

I'm just trying to catch it before it develops into a bigger problem.

If anyone else out there has any suggestions or has experienced this, please let me know.

Well, the horn works, and all is well. I just went over the 200,000 mile mark, and I'll just keep going. Now it's time to figure out why my AC died. I don't hear it engaging, so eventually I'll take a look at the magnetic clutch etc... I'm not that concerned about the AC, but it sure is nice to have.

Over and out for now.

Thanks for everyone's input.

Huntington Beach, Ca.

04-24-2010, 04:20 PM
Today I finally got the CEL again, and the same DTC appears on my hand-held code reader, 0401, insufficient EGR flow.

I've had the clicking all along, and I had already eliminated the EGR valve as the culprit, although I still believe that it's the EGR valve I hear opening and closing, possibly due to erroneous signals from the ECM, which could be getting bad input from one of the other sensors in the same feedback loop.

I have to travel for work on Monday and can't be without my car, but, I got a chance to take it in for a quick look by my local mechanic down the street, to see if their scan-tool could dig deeper than my hand-held reader.

I told them the story and that I had already eliminated the EGR valve and gasket as possible causes.

They just called me and said that they need to remove and clean the entire throttle body since something is clogging the EGR path.

For $170.00 total cost, I agreed to have them do it since they can do it quicker than I, and I need my car back ASAP. They've done work for me in the past, and I have a very good rapport with them, so it isn't like walking in as a first-timer to an unknown establishment.

It makes sense, since the EGR valve would likely be getting signals to open and close if the path is clogged, since the exhaust gas isn't getting recirculated to be burned more completely and lessen emissions.

My biggest worry is that if I let this go on too long, it could ruin both of my catalytic converters and cost me a lot more money. I suspect that one or more sensors (02 sensor?) is communicating that the EGR needs to open up and recirculate the exhaust since it's too rich to be spewing out the back.

We'll see how it goes. I should have it back within a few more hours. I'll post the results soon.

Huntington Beach, Ca.

04-24-2010, 07:46 PM
The local mechanic said that they had to clean out lots of deposits on the throttle body. I guess 200,000 miles will do that.

The thing is, I still hear that faint clicking. I'll have to see if the CEL comes on again in the near future with DTC 0401.

It's very possible that the faint clicking sound and the EGR CEL issue are unrelated.

I called and told them I still hear the clicking, and they said that it's also possible that the clicking I'm hearing is from the "Canister Purge Valve".

I haven't found any info on that yet (?), but I did find a "canister" as part of the fuel system, though the shop manual doesn't give any info on it except for a sketch of it (at least that's all I've found so far).

I'll have to see how it goes.

Over and out for now.


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