2003 Escalade Ext With Ekectrical Gremlin, Help If You Dare

beav626 · September 22, 2011

Cruising down the highway a while back 60mph on cruise control. I hit a expansion joint and it jolted me and the truck.

immediately I lost radio and doors unlocked and AC quit.

Radio came back on quickly and I locked the doors. Thats when I realized I was blowing hot air (no AC)

I took my exit and as I slowed I felt like I lost Power Steering.

I parked the truck and turned her off. Started her up and she started fine but idle seemed lower than normal. So I went in the store and came back out. When going slow if I turn the wheel my idle drops too low and kicks off my AC.

Got her home. Checked the Freon level- Its Good.

Checked the idle with HPTuners and it is 550 which is what the tune called for.

Disconnected battery and let the truck sit for an hour.

The air-filter is dirty so Im going to replace that.

No Lights or leaks... Checked O2 sensors through HP Tuners and they are performing normal.

No Mods except for Flowmaster Exhaust and a tune.

2003 Escalade 6.0

What the heck happened.

Any kind of bump will cause the truck to short out. Short out includes: loss of crusie control, Doors unlocking, AVG MPG freezes, AC compressor kicks off, Engine hesitates. But I do not loose my radar detector (Tied into HVAC)

Fast Forward a while...

I have found a broken ground (From the Hood to firewall) and replaced it. Checked all other engine and front grounds and they are good.

I replaced the Ignition Switch

Wiggle test reveals nothing.

However tonight I Think I Isolated the problem... (Yes Im still at it)

The Short is happening much, much less frequently

I found a stretch h of road that would trigger the short. And I drove it a few times tonight. I found that by pushing in on the key (Towards the column) It wouldn’t short out.

If I let go of the key It would short out.

I've already replaced the Ignition Switch, so could it be the key mechanism? If I jiggle the key I cannot duplicate it, only over rough bumps..

Thanks in advance

nickvrebel · September 22, 2011

The electrical short could be related to the connections to the cylinder switch, wouldn't hurt to check it out. How many keys do you have hanging from that key ring? Excessive weight there has been known to cause issues on vehicles for quite some time.

the a/c may be coincidental - my sister-in-laws Tahoe had that same issue. I checked the throttle body and it was filthy. Cleaned the throttle plate front and back and it fixed the a/c issue. What was happening was the 2003 trucks have electronically controlled throttles and no Idle Air Control Valve. The throttle plate was sticking slightly and when the motor asked for more air it wasn't getting it. That triggered a slightly lower idle condition momentarily (you probably would have a hard time detecting it on the screen for HP Tuners, it doesn't update fast enough). That triggered the "stall saver" feature (this can be adjusted in HP Tuners, but you shouldn't need to).

About "Stall Saver"

it's a fail safe. if the idle hits a certain low the stall saver takes over and shuts down all accessories (a/c, etc.) to save the motor from stalling. I learned a good bit about this feature when tuning a friend's truck. We had swapped in a 6.0L with a choppy cam and I was tuning it to run correctly. I had the idle issues working fine, but we pulled into Sonic drive in and noticed the a/c wasn't working anymore. A few tweaks to the stall saver setting and I had it. The main issue I had with this was the choppy cam really messes with idle speed. There should be no need to change this for a stock cam truck.

beav626 · September 22, 2011

By cylinder switch to you mean ignition switch? Or the actual tumbler that the key goes into.

I have replaced the ignition switch and that is good. I dint see how the cylinder can malfunction. Also I only have my truck key, home key, and fob.

As far as idle. That makes sense. I will pay attention to that.

jrrod2004 · September 22, 2011

By cylinder switch to you mean ignition switch? Or the actual tumbler that the key goes into.
I have replaced the ignition switch and that is good. I dint see how the cylinder can malfunction. Also I only have my truck key, home key, and fob.

As far as idle. That makes sense. I will pay attention to that.

Two things jump out at me:

Ignition cylinder as noted above (check all existing connections and make sure they are clean and tight)

main battery connector to junction block (fuse boxes) off the main line. i had an intermittent condition that went away when I installed the "Big Three". It came back as soon as I took off the megafuse. Found the main positive wires were loose. Cleaned them up and retightened. no issues since.

beav626 · September 22, 2011

What is the "big three"

yz2009 · September 22, 2011

Its adding larger gauge wire in a couple place in the engine compartment. I used 0/1 gauge when i did my subwoofer instal. It consists of:

Alternator to battery

Engine ground (engine to chassis)

Battery to main fuse box

beav626 · October 4, 2011

Ive had a subwoofer in my truck for a long time and never a problem. I checked all the locations you mentioned and all looks good there.

It is not near as bad as before but still happens over rough stretches of roads.

Trav_13 · October 4, 2011

Ive had a subwoofer in my truck for a long time and never a problem. I checked all the locations you mentioned and all looks good there.

It is not near as bad as before but still happens over rough stretches of roads.

How about the radio? Is yours factory? I had a guy I know that had an internal short in his radio and it would create some of the conditions you are describing....

beav626 · October 4, 2011

I have a pioneer Z110 that has been great since day one.

What I cant figure out is that the short was really bad and very common driving around town. When I fixed the ground cble going fro the hood to the firewall it got better but not gone completely.

I bought a smaller gauge wire, would that matter on a ground wire?

jrrod2004 · October 4, 2011

I have a pioneer Z110 that has been great since day one.

What I cant figure out is that the short was really bad and very common driving around town. When I fixed the ground cble going fro the hood to the firewall it got better but not gone completely.

I bought a smaller gauge wire, would that matter on a ground wire?

not really, gauge on ground doesnt matter if you arent planning to run anything big on it. i would make sure that all the connections are clean, have dielectric grease on em and nice and snug. it is possible that a wire could be damaged. If you can, get a multimeter and measure resistance in the wire. I dont know what else it can be.

beav626 · October 24, 2011

after 2 weeks its back again... It is much worse now. It is causing havoc on the engine and tranny along with the gauge and door locks. ih I am accelerating and it happens the engine hesitates and the tranny forgets to shift. I touch the breaks and it works again.

Also I noticed in the instrument cluster the Sifter indicator is not working, it wont show which gear I'm in, until I restart the truck.

Im wondering if it could be the PCM... Any help is appreciated

beav626 · October 26, 2011

Bingo---Took it to local dealer today and we were talking about it and both agreed it to be the BCM... but he wanted to have someone diagnose it to be sure... I get a call back later saying the BCM is fine it is just one of the grounds on the back of the block... (I thought I checked all those) Anyways that’s the good news and truck is ready except the say i need to replace the pitman arm, Idler arm, and outer tie rod... (At least its not electrical)

jwh463 · October 26, 2011

Cruising down the highway a while back 60mph on cruise control. I hit a expansion joint and it jolted me and the truck.

immediately I lost radio and doors unlocked and AC quit.

Radio came back on quickly and I locked the doors. Thats when I realized I was blowing hot air (no AC)

I took my exit and as I slowed I felt like I lost Power Steering.

I parked the truck and turned her off. Started her up and she started fine but idle seemed lower than normal. So I went in the store and came back out. When going slow if I turn the wheel my idle drops too low and kicks off my AC.

Got her home. Checked the Freon level- Its Good.

Checked the idle with HPTuners and it is 550 which is what the tune called for.

Disconnected battery and let the truck sit for an hour.

The air-filter is dirty so Im going to replace that.

No Lights or leaks... Checked O2 sensors through HP Tuners and they are performing normal.

No Mods except for Flowmaster Exhaust and a tune.

2003 Escalade 6.0

What the heck happened.

Any kind of bump will cause the truck to short out. Short out includes: loss of crusie control, Doors unlocking, AVG MPG freezes, AC compressor kicks off, Engine hesitates. But I do not loose my radar detector (Tied into HVAC)

Fast Forward a while...

I have found a broken ground (From the Hood to firewall) and replaced it. Checked all other engine and front grounds and they are good.

I replaced the Ignition Switch

Wiggle test reveals nothing.

However tonight I Think I Isolated the problem... (Yes Im still at it)

The Short is happening much, much less frequently

I found a stretch h of road that would trigger the short. And I drove it a few times tonight. I found that by pushing in on the key (Towards the column) It wouldn’t short out.

If I let go of the key It would short out.

I've already replaced the Ignition Switch, so could it be the key mechanism? If I jiggle the key I cannot duplicate it, only over rough bumps..

Thanks in advance

I had a 2005 (05/05-7/11) Envoy with the 5.3l and had a similar issues last year, cruise cut off then the doors would lock unlock. The gear indicator would move from p to D repeatedly then within 5 seconds all is well and you reset the cruise and all works. Dealer replaced; ignition switch, liftgate module, body control module, neutral safety switch, abs wheel sensors and when all else fails they replaced the PCM (eng computer) as a 'courtesy'. Then 2 weeks later it happened again. They put a recorder in it and it happened again. This time dealer said recorder indicated PCM was loosing connection with transmission and thus didnt know what gear it was in ..doors unlocking cruise shutting off etc. They replaced the transmission 'computer or module' and it was fixed and never had another problem.