47re manual od switch? - Competition Diesel.Com

gododge99 · 04-06-2017, 06:24 PM

Found a thread on here from a while back about doing a manual switch to engage od. Truck is a 99 p pump 24v. After doing the swap I lost od. I'm using a 12v tps and it still will not go in. Anyway I ran a switched ground to the b21 pin on the tcm. I went and tested it and it went into od for a split second then kicked out and limped the trans. Is there any other wire I need to run? To keep it from limping the trans?

jasonc · 04-06-2017, 06:29 PM

I don't know about running them thrue the ecm but if you supply a ground to the OD wire at the three wire plug on the trans it will bypass all and engage. Lockup works correct?

BigPapa · 04-06-2017, 08:12 PM

If you get a Krazy Karl's APPS kit you can put the APPS back on the P-pump and all will be as it was.

If the pin you speak of is commanding the PCM and not the tranny directly, it is a momentary ground, not a constant ground. I'm not certain but I imagine putting a constant ground to it could cause the issues you describe. The PCM "thinks" something's wrong.

gododge99 · 04-06-2017, 11:21 PM

Got it figured out, cut the brown wire at pcm gave 12v to the pcm side of the plug and switched ground to the trans side. Works like a dream

04-06-2017, 06:24 PM	#1
gododge99 Name: gododge99 Title: Truck In Shambles Status: Not Here Join Date: Feb 2009 Location: Nor Cal Member`s Gallery Posts: 242	47re manual od switch? Found a thread on here from a while back about doing a manual switch to engage od. Truck is a 99 p pump 24v. After doing the swap I lost od. I'm using a 12v tps and it still will not go in. Anyway I ran a switched ground to the b21 pin on the tcm. I went and tested it and it went into od for a split second then kicked out and limped the trans. Is there any other wire I need to run? To keep it from limping the trans? __________________ P Pump 24V Allied Diesel Performance

04-06-2017, 08:12 PM	#3
BigPapa Name: BigPapa Title: Truckless Status: Here Join Date: Jan 2008 Location: Springfield, TN Member`s Gallery Posts: 5,034	If you get a Krazy Karl's APPS kit you can put the APPS back on the P-pump and all will be as it was. If the pin you speak of is commanding the PCM and not the tranny directly, it is a momentary ground, not a constant ground. I'm not certain but I imagine putting a constant ground to it could cause the issues you describe. The PCM "thinks" something's wrong. __________________ Scott 2003 Avalanche Z71 Common sense is like deodorant. The people that need it most never use it. Last edited by BigPapa; 04-06-2017 at 08:19 PM.

04-06-2017, 11:21 PM	#4
gododge99 Name: gododge99 Title: Truck In Shambles Status: Not Here Join Date: Feb 2009 Location: Nor Cal Member`s Gallery Posts: 242	Got it figured out, cut the brown wire at pcm gave 12v to the pcm side of the plug and switched ground to the trans side. Works like a dream __________________ P Pump 24V Allied Diesel Performance

04-06-2017, 06:29 PM	#2
jasonc Name: jasonc Title: Too Much Time Status: Not Here Join Date: Nov 2009 Member`s Gallery Posts: 4,412	I don't know about running them thrue the ecm but if you supply a ground to the OD wire at the three wire plug on the trans it will bypass all and engage. Lockup works correct?