Security Issues

podunk · October 10, 2006

Hello all, Having issues with a 2000 GMC Yukon Denali.

Intermittently I go to start and it will fire up and immediately shut down.

According to documentation the fuel pump is being shut off. No rhyme or reason/trends.

Occasionally waiting 20 mins will reset but usually not. Stranded several times now. What could be the culprit, or how to work around?

WTFO

Thanks in advance,

podunk

GM-Tech · October 10, 2006

The security systems shut off the injectors, it does not turn off the fuel pump.

We had some problems with the passkey (security) harness back then. It's part of the ignition switch so you'd have to replace that to get the passkey harness.

BTW, a theft system probem will NOT cause a stalling condition once the engine is running. It will only start and stall immediately or not start at all. So if it stalls while driving, it ain't the security system.

Knowing what codes are stored would help. Security system codes will not turn on the check engine light, so don't judge whether or not there are codes just because the SES light may not be on.

podunk · October 10, 2006

The security systems shut off the injectors, it does not turn off the fuel pump.

We had some problems with the passkey (security) harness back then. It's part of the ignition switch so you'd have to replace that to get the passkey harness.

BTW, a theft system probem will NOT cause a stalling condition once the engine is running. It will only start and stall immediately or not start at all. So if it stalls while driving, it ain't the security system.

Knowing what codes are stored would help. Security system codes will not turn on the check engine light, so don't judge whether or not there are codes just because the SES light may not be on.

<{POST_SNAPBACK}>

Injectors! Roger that.

No problems while engine is running. Only when engine is shut off for 3 min/30mins/3hrs/3days etc. Go to start it and fires/runs for about 1 sec and acts like no fuel.

Yes, codes would help.... Apologies

So, if I understand correctly, codes first, then prob new ignition/set of keys?

Thanks again, you guys

GM-Tech · October 11, 2006

So, if I understand correctly, codes first, then prob new ignition/set of keys?

I didn't say anything about keys. They have nothing to do with it. Ignition switch, but understand that with the limited amount of information I have, that's just an educated guess based on past experiences.