I have owned my Monte for three years and have never really had a problem with it. Recently and almost randomly, when I get into my car to leave, my car will refuse to start. If i turn my ignition to the on position, the lights come on, the blower motor kicks on, and the radio works, but when I fully turn my key to the on position nothing happens. If I'm persistent and keep at it for a minute or two, the vehicle will eventually start fine as it normally would. Also, as I'm driving, my battery light will come on and my voltmeter will randomly drop down to eight (the bottom of the guage) and back up to around fourteen where it should be. I know that this cannot be alternator related because even if my voltage regulator were going out, the voltmeter should still read at least 11 to 12 volts. Also, my stereo lights will randomly become dim as if I had turned on my headlights and my stereo will randomly lock. My air conditioning also fails sometimes, but only when I have had problems getting it to start. For example, I had a difficult time getting the vehicle to start the other day ( It was sweltering too I might add) and when I finally got my car started, the A/C would not work. The blower worked fine but only hot air came out. When I arrived at my parents house I shut the car off and went in to visit. I left around an hour and a half later and when I got in my car it started fine and best of all, My A/C worked for a bit. After around five minutes of driving my voltmeter dropped out again and as soon as it did I lost my A/C again. I might also add that I almost never have these sorts of problems early in the day or later in the evening. It seems to always happen when the vehicle has been in the sun for some time. My interior is black and it gets very very hot in the sun. This leads me to believe that it is something in the interior. My security light also flashes on and off when these things happen and occasionally, the message center will read service vehicle soon. Any help with this would be greatly appreciated. Please Help.

 

ignition switch sounds like its faulty, the a/c not working when its running is a little odd though. there could be another problem with the underhood fuse block but that could all be related to a bad ign switch. its a known weak point of gm cars and trucks so i'd concentrate on that.

 

Thanks, I had an idea that it may either be the Ignition cylinder or the BCM but, as I am not a mechanic, was not sure. I will try the cylinder first.

 

I replaced the switch with a new one and it is still a no go. Any ideas on what else it might be? Also, the car started up just fine immediately after install without me coding it. Is that normal? The security was flashing while driving immediately after I changed the switch but today it just stayed on

 

possibly leads me to believe battery connection overall. i could see your ac not working because the clutch cant enguage due to your battery connection. check all the wiring from your positive terminal on and look for corrosion or loose connection. even the ground wiring going back to the battery.

 

I checked all of my connections and they appear to be fine. My radio also reads cal err randomly now. I assume that means Calibration Error. Also, Service Engine Soon Shows up in my message center randomly now.

 

I checked my dtc's today and got a p1626. Here is what it reads.

The body control module (BCM) produces the theft deterrent fuel enable signal when ignition is ON and the proper key resistor pellet is sensed. The powertrain control module (PCM) monitors the fuel enable signal during crank. If the proper signal is present on the theft deterrent fuel enable circuit, the PCM enables fuel delivery to allow the engine to start. If the PCM detects that the fuel enable signal is not present or incorrect while the engine is running, DTC P1626 will be set. DTC P1626 can cause a no-start condition or normal operation depending on when the loss of the fuel enable signal was detected. The engine will continue to start and run if the condition that set DTC P1626 occurred after the BCM sensed the proper key resistor pellet and signaled the PCM to continue fuel delivery. The engine will start and immediately stall if the condition that set DTC P1626 occurred before the BCM sensed the proper key resistor pellet. With this condition present, the PCM will inhibit fuel delivery and the BCM will disable the starter.

I am so confused.......

 

Here is the dtc history from my car courtesy of my buddy with hp tuners.

[PCM] P0133 - HO2S Slow Response Bank 1 Sensor 1 (SES) (Old) (History) (Current) (Immature)
[PCM] P1626 - Theft Deterrent Fuel Enable Signal Not Received (Pending) (History) (Immature)
[PCM] U1064 - Loss of Communications with DIM (Pending) (History) (Immature)
[Brake] C1245 - (History)
[Unknown] U1016 - Loss of Class 2 Communication with VCM (History) (Immature)
[Unknown] U1000 - Class 2 Communication Malfunction (History) (Immature)
[Unknown] U1255 - Class 2 Communication Malfunction (History) (Immature)
[Unknown] B1440 - (History) (Immature)
[Unknown] B1477 - (History) (Immature)
[Unknown] B1507 - (History) (Immature)
[Unknown] B2582 - (History) (Immature)
[Unknown] B2618 - (History) (Immature)
[Unknown] B2655 - (History) (Immature)
[Unknown] B2958 - Security System Sensor Data Circuit High (History) (Immature)
[Unknown] B2960 - Sec Sys Sensor Data Incorrect but Valid (History) (Immature)
[Unknown] B2964 - (History) (Immature)
[Unknown] B3031 - Key Decoder Device in Assem Learn Mode (History) (Immature)
[Unknown] B3033 - Security System Indicates Tamper (History) (Immature)
[Unknown] B3128 - (History) (Immature)
[Unknown] B3138 - (History) (Immature)
[Restraints] U1000 - Class 2 Communication Malfunction (History) (Immature)
[Restraints] U1064 - Loss of Communications with DIM (History) (Immature)
[HUD] U1000 - Class 2 Communication Malfunction (History) (Current) (Immature)
[HUD] U1064 - Loss of Communications with DIM (History) (Immature)
[HUD] U1064 - Loss of Communications with DIM (History) (Immature)
[Entertainment] B1001 - Option Configuration Error (History) (Current) (Immature)
[Entertainment] B1780 - Theft Lock Enabled (History) (Current) (Immature)
[Entertainment] U1000 - Class 2 Communication Malfunction (History) (Current) (Immature)
[Entertainment] U1064 - Loss of Communications with DIM (History) (Immature)
[Personal Comm.] U1000 - Class 2 Communication Malfunction (History) (Immature)
[Personal Comm.] U1064 - Loss of Communications with DIM (History) (Immature)
[Personal Comm.] B1000 - ECU Malfunction (History) (Immature)


Any Help Translating would be greatly appreciated.

 

Sigh....... Bump

 

Bump......