A complex electrical journey to paddle shifter goodness.

I've been performing a lot of repairs and alterations to the Cohete Rojo's electrical systems. Since this truck will be used year round, I decided to install a passenger battery. The passenger battery was deleted when I took ownership of this truck. The more digging I did on this truck, the more the wiring bothered me.  

Thus far, I have re-configured and repaired the following electrical systems;

  • New battery cables.
  • Added a passenger battery with an eBay sourced used battery tray.
  • Added a crossover battery cable.
  • Flex a lite fans have been rewired and tied in to ac compressor signal wire.
  • Quadzilla has been rewired.
  • Airdog has been rewired.
  • Ignition on power source from the automatic shutdown relay has been chosen to provide power to the PCS standalone transmission controller, PCS paddle shift communication module and PCS paddle shifters. 
  • An additional fused relay has been installed and is triggered from the ASD relay. 
  • I utilized this power source because it is always live with key on. (Provides ECM power)

For PCS/ paddle shifter integration, a bit of resourcefulness is required. To implement paddle shifters, it requires the following;

  • Standalone PCS transmission control module (TCM/TCU) I used a PCS 2800 standalone for this installation. 
  • TCM Wiring harness modifications for better fitment. 
  • Wiring harness installation to communicate with TPS, MAP, ignition on, OD cancel switch, sensor ground, and CKP signal.
  • To execute the TCM harness implementation, the most conducive area was at the PCM behind the turbocharger. Multiple connections were utilized on the C1 and C3 connectors. It was decided to wire the "manual mode" PCS wire in series with the factory OD off button. When the TCM is in manual mode, the dash will illuminate "OD OFF"
  • Implementation of paddle shifter communication module. This requires configuring the yellow wire to ignition on power, black wire to chassis ground and connecting the white with red tracer/ white with black tracer wires to the TCM harness.  
  • Airbag resistance measurement.
  • Wiring modification to the clockspring circuit to send power and ground signals to paddle shifter unit. Use of the cruise control wires or airbag wires for this function.
  • The clockspring needs slight modification on 94-02 rams. There are two  spring loaded tabs that keep the clockspring locked when a steering wheel is not bolted to the column. Presumably, this is to keep the clockspring from going out of centered sequence. In the absence of a factory steering wheel, the two tabs are not depressed and the clockspring will not rotate. I simply cut the tabs out and removed them. Now the clock spring is free bird. 
  • Horn circuit rewire.
  • NRG steering wheel adaptor.
  • Mounting of the TCM.
  • Mount the wheel and paddles, and test for functionality. After all of this work, we have a pulse on the paddle display!
  • After the TCM was powered up, I plugged in with my laptop to set digital input 12 to a momentary toggle with inverted logic. This ensured the manual mode on the TCM functioned in concert with the "OD OFF" light on the dash. Had this step not been executed, the operation would be opposed I.E. "OD OFF" light on when in auto shift mode and off in manual mode. 
  • TPS calibration was necessary to get a 100% reading from our 217K mile 3.56V sensor reading. This ensures shift points will be linear with throttle position and vehicle speed.
  • I also had to set some shift limits, as the calibration was not 100% configured for manual operation. I'll input the rest later, but the fact that the paddles went to 5th was driving me bonkers. That bit is rectified...


Since summer can be intolerable in the northeast, I also decided to install new air conditioning components from rockauto as the existing ones were bypassed and open to the atmosphere for, well who knows how long.

This consisted of;

  • Suction and pressure lines 
  • Condenser
  • Evaporator (once we install the new dash from Geno's garage)
  • Receiver/ drier
  • Compressor
  • Pressure switches.


Now that the brunt of the electrical is finished, I can focus on getting my stage two automatic 47 bolted in. I'll keep wrenching and keep you updated as progress ensues....

Until the next post....

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