03 Chevy S10 tach wire

2003 Chevrolet S10 4.3L extended cab 2WD.

I have connected the tach input wire to the white wire on the coil and I seem to be having some problems. I am getting an intermittent check engine light (usually turns on after a remote start). I disconected the wire, just to see, and the module reacts the way I had expected, it starts and shuts down within seconds. I tried using a diode, preventing the coil from 'seeing' the module. Oddly, the starter would not disengage. Is there a better place to tap? I looked on the instrument cluster but I couldn't find the right signal, and don't have a good schematic. One other thing I foud odd was the istruments don't indicate until I put the ignition in run, manually.

After some searching online, It looks as if the tach wire I assumed was incorrectly connected is not the problem. I used the following charts to hook up the remote start:

https://www.the12volt.com/installbay/forum_posts.asp?tid=23415

I pulled the following codes from the vehicle:

P0740 TCC Enable Solenoid Circuit Electrical

I found this on the internet:

- this can result in the converter staying in lock-up mode and feeling like the engine has no power or is starting off in a higher gear - it can be because the converter is bad or it could be a switch in the transmission causing a false signal - either way it will have to be checked by a dealer as most shops are limited in the availability of transmission software for their scanners. Most transmissions shops are also limited and just want to replace parts or sell an overhaul. Also there is a default condition on most electronic transmissions which put them in 2nd gear default when the PCM sees a transmission fault - this locks the trans in 2nd gear only allowing you to get to a dealer - this could explain why it has no power - also when you cycle the key on and off the default shift condition can go away until the PCM sees the malfunction again....

and

...may illuminate the MIL and produce a condition that causes the transmission to stick in 3rd gear. The instrument cluster may become inoperative, as well. When you check the codes, one or all of the following DTCs may be set in memory: P0740, P0753, P0758, P0785 and P1860.

Can anyone help me determine which ignition harness wire I may have mistaken.

did you power up the 2nd ingition wire the white one coming from your ingition harness

WIRING INFORMATION - CHEVROLET / S-10 PICKUP / 2003 / Remote Start

12volts  red  +  ignition harness Starter  yellow  +  ignition harness Second Starter  N/A     Ignition  pink  +  ignition harness Second Ignition  white  +  ignition harness Third Ignition  N/A     Accessory  orange  +  ignition harness Second Accessory       Keysense       Power Lock  lt. blue  +  brown plug at BCM Notes: The BCM (Body Control Module) is located to the right of the accelerator pedal below the radio. The plugs on the BCM face towards the driver side. Power Unlock  white  +  brown plug at BCM Notes: The BCM (Body Control Module) is located to the right of the accelerator pedal below the radio. The plugs on the BCM face towards the driver side. Lock Motor  gray  5wi  driver kick panel Unlock Motor  tan  5wi  driver kick panel Parking Lights+  brown  +  lt. blue plug at BCM Notes: The BCM (Body Control Module) is located to the right of the accelerator pedal below the radio. The plugs on the BCM face towards the driver side. Parking Lights-  white  -  lt. blue plug at BCM Notes: This wire will not test when using the headlight switch. This wire is triggered by the DRL system. To meter the wire, start the car with the parking brake set, when the brake is released this wire will go to ground. The BCM (Body Control Module) is located to the right of the accelerator pedal below the radio. The plugs on the BCM face towards the driver side. Hazards       Turn Signal(L)       Turn Signal(R)       Reverse Light       Door Trigger    -  purple plug at BCM Notes: Use tan for the driver door located in pin B4, orange for the passenger door located in pin B2. Use both wires and diode isolate. The BCM (Body Control Module) is located to the right of the accelerator pedal below the radio. The plugs on the BCM face towards the driver side. Dome Supervision  use door trigger     Trunk/Hatch Pin  N/A     Hood Pin       Trunk/Hatch Release  N/A     Power Sliding Door  N/A     Factory Alarm Arm       Factory Alarm Disarm  lt. green  -  purple plug at BCM Notes: The BCM (Body Control Module) is located to the right of the accelerator pedal below the radio. The plugs on the BCM face towards the driver side. Disarm No Unlock  see factory alarm disarm     Tachometer  white  ac  PCM Notes: The PCM (Powertrain Control Module) is located on the passenger fender. On the 2.2L the wire is in a black 80 pin plug pin 10, and on the 4.3L the wire is in a red 32 pin plug pin 20. Wait to start  N/A     Brake Wire  white  +  steering column Parking Brake       Horn Trigger  black  -  steering column Notes: Also found in the brown plug at the BCM on vehicles with a factory alarm. Memory Seat 1       Memory Seat 2       Memory Seat 3       Interface Module: Category: Immobilizer Bypass Required: Yes Type: Passlock II Part #: 556LW Alternate Part1 #: 555LW Alternate Part2 #: DesignTech 20402 Alternate Part3 #: DesignTech 29402 Notes: Interface Module: Category: Door Lock Interface Required: No Type: N/A Part #: N/A Notes: Interface Module: Category: Combo Interface Required: Yes Type: Data Bus Part #: 457GW Notes: Can use the 457GW to bypass the Passlock II, but it will not control the door locks on this model year.

I had tested the small white wire, and I have disconnected and tested again. It is the second ignition wire. Just to make sure I tested the pink/white wire on the remote start relay module: No voltage at all was present during the start cycle. Is the second ignition wire from the module used for only more current capability or is the timing different?