Command Start 290i-C trouble and need documentation

[kabby]

Hi all!

I am totally new to this sort of communication, so here goes...

I purchased a '95 Yukon with a Command Start 290i-C installed in it. It has worked flawlessly for a year or so, but now only makes a funny noise in the control box whenever I hit a button. I have removed and opened up the control box and everything looks sound (no "hotspots" or signs of shorting etc.). When I hit button 1, I get a buzzing sound from the relays and nothing else happens. When I hit button 2, i get the same sounds from the box, but the locks do operate. I don't notice any of the park lights flashing though. They did before.

I did not receive any CS documentation with the vehicle and would like to troubleshoot the problem. I welcome any and all assistance with this. I have tried replacing batteries, have checked the fuses on the unit's main power feed wires (they're good), and have tried turning the unit's toggle switch off for a long period of time in a feeble attempt at resetting the unit. No luck!

I understand that the company has gone under/sold out/ whatever and have had no luck searching the web for info, except being put on to this site. From what I have read, there are a number of knowledgeable/helpful people out there.

I leave for holidays on Sunday and wouldn't mind having it fixed before then, if possible. If you have any ideas or have access to documentation, I'd love to hear from you!

[Strugari]

PM me and I will send out the schematic for the 290i.:thumbsup:

[topgun_tb]

Hi folks...I'm new to the forum and looking for some help. I have a 92 Chev 1/2 ton with a Command Start (I think 250i or 260i) model. It has worked great for years, but I let the truck sit this summer and the battery died. Well, I put a charger on it it for a few minutes and in my haste, I operated the door lock/unlock button on the Command Start remote...I heard the locks go 'thunk' but then the COmmand start seemed to just die...and there was a smell of burned insulation in the passenger compartment. Something must have gone 'poof' as it seems the Command start unit is totally dead..(i.e. not even the blinking red LED). Question:

i) where is the CommandStart main module located? (under the dash)? I must admit I don't even know what it might look like.
ii) if I can locate the main module, are there any on-board fuses that I can check?

I have the laminated 'quickie' programming and operation guide and the 8.5" x 11" programming and wiring guides, so I think I can trouble shoot it if I can be pointed in the right direction.

Any help would be appreciated...

[topgun_tb]

...more info...

OK...I finally found the Command Start (CS) module...way up under the dash buried in amongst a number of wiring harnesses. I also found a couple of in-line fuses that look like add-ons (i.e. non-OEM factory). I checked one..it was a 30A on the 12AWG red wire (leading to the CS module as best as I could tell)...it was blown! So, I only had a couple of 10A fuses in my junk bin, so I put one of those in just to see if anything would happen...and it too went poof. So, I am beginning to think there is a dead short on the circuit...(the 10A blew without operating anything...i.e. door locks or starter). Any ideas where a dead short on this circuit could be?

Any insights would be appreciated...

[DoubleLP]

Originally posted by kabby
Hi all!

I am totally new to this sort of communication, so here goes...

I purchased a '95 Yukon with a Command Start 290i-C installed in it. It has worked flawlessly for a year or so, but now only makes a funny noise in the control box whenever I hit a button. I have removed and opened up the control box and everything looks sound (no "hotspots" or signs of shorting etc.). When I hit button 1, I get a buzzing sound from the relays and nothing else happens. When I hit button 2, i get the same sounds from the box, but the locks do operate. I don't notice any of the park lights flashing though. They did before.

I did not receive any CS documentation with the vehicle and would like to troubleshoot the problem. I welcome any and all assistance with this. I have tried replacing batteries, have checked the fuses on the unit's main power feed wires (they're good), and have tried turning the unit's toggle switch off for a long period of time in a feeble attempt at resetting the unit. No luck!

I understand that the company has gone under/sold out/ whatever and have had no luck searching the web for info, except being put on to this site. From what I have read, there are a number of knowledgeable/helpful people out there.

I leave for holidays on Sunday and wouldn't mind having it fixed before then, if possible. If you have any ideas or have access to documentation, I'd love to hear from you!

Sounds to me like it is in "Valet" mode. I am not sure how to get it out of valet mode....but that what me thinks is wrong with it.

[DoubleLP]

Originally posted by topgun_tb
...more info...

OK...I finally found the Command Start (CS) module...way up under the dash buried in amongst a number of wiring harnesses. I also found a couple of in-line fuses that look like add-ons (i.e. non-OEM factory). I checked one..it was a 30A on the 12AWG red wire (leading to the CS module as best as I could tell)...it was blown! So, I only had a couple of 10A fuses in my junk bin, so I put one of those in just to see if anything would happen...and it too went poof. So, I am beginning to think there is a dead short on the circuit...(the 10A blew without operating anything...i.e. door locks or starter). Any ideas where a dead short on this circuit could be?

Any insights would be appreciated...

Try unplugging the brain first then replacing the fuses. If it still blows the fuses you might have a bare wire somewhere that is touching metal.

If not, plug the brain back in. If it blows the fuses then, then there is a problem with the brain itself. You might have caused a short in it somewhere when you boosted the truck.

Hope this helps.

[Strugari]

Try unpligging the unti, and then install the fuse to see if it blows out. If it does not then there is a short in the unit. If it does blow the fuse, the power wire is grounding out somewhere.
Let us know how you make out.:thumbsup:

[topgun_tb]

Thanks everyone. I concluded that the short was between the fuse holder and the CS module.....so after inspecting the 12AWG (red) wire and finding it well insulated and in good shape, I figured the problem must be in the CS module. So, I unplugged the various connectors and removed the module, and took the cover off the module. Low and behold, there on the circuit board was a 1N6276A transient surge suppressor that looked damaged...I figure it took a hit somehow and failed rather catastrophically (outer shell of it is cracked open). So, I guess I need to see if I can get another one and solder it in. I have a pic of the board (with failed component) if anyone is interested, but the file size is too large to post here. Maybe I can another pic on the low quality setting of my camera. Anyhow, thanks for your help...I think I have found the problem, and I now need to do something about it!
Cheers,

[topgun_tb]

Dear Strugari...you seem very knowledgable on the CS products and I have another query for you. I managed to replace the failed transient voltage suppressor on the board inside the module, so tomorrow I will reinstall the module under the dash and hook up the connectors. Will I have to program anything to make it work, or will it work as it did before the device failure? Also, my pin switch under the hood broke off about 3 years ago, so I think I just grounded the wire (if memory serves me correctly). If I have to program the module in any way, will I need 'on-off' capability of the pin switch to enter-exit any of the programming modes? I guess I could just ground it via a switch and simulate the pin switch. Any help would be appreciated.

thanks,

[topgun_tb]

..k...in case anyone is interested, I removed the failed transient voltage suppressor from the main circuit board on the Command Start module , and soldered a new one in. I reinstalled the module in the vehicle, and like magic, it works fine. Moral of the story: If your Command Start just stops working and blows the main inline fuse, check the main circuit board for a failed transient volatge suppressor. It's a $0.91 part that take 5 minutes to replace.

Regards,

[Strugari]

Thanks for the info. I was away fopr a couple days, so I did not get back to you sooner. :thumbsup: