I believe I have a small case alternator from a 2020 GMC Savanna. Actually 110 amps. Not 105 as I wrote earlier.
I haven't seen a need for a bigger alternator at the moment since I am not running electric fans.
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I believe I have a small case alternator from a 2020 GMC Savanna. Actually 110 amps. Not 105 as I wrote earlier.
I haven't seen a need for a bigger alternator at the moment since I am not running electric fans.
I've done a lot of "big engine in small space" type swaps. Something I've learned is that it is impossible for even the fanciest electric fans in the world to come anywhere close to the performance of your basic thermostatic clutch fan. The thermostatic clutch fan is brilliant- True KISS.
Electric fans can be the Achilles heel of your build. And my experience has been the harder you try to overbuild an electric fan system with aftermarket stuff the less reliable and harder to fix it becomes.
If there is a straightforward path to using thermostatic clutch fan in a build I highly recommend it.
Electric fans can be the Achilles heel of your build. And my experience has been the harder you try to overbuild an electric fan system with aftermarket stuff the less reliable and harder to fix it becomes.
If there is a straightforward path to using thermostatic clutch fan in a build I highly recommend it.
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I dont think that code is related much to the alternator. GM throttle body plugs do not like vibration. What is your battery voltage with fans on at idle?
To add to amperage question the alternator at low idle doesnt put out the rated amps.
Thanks guys. I ran new 2 gauge ground wires (cylinder block to fire wall, block to chassis, gm stock ground from battery to block). Also tapped a ground wire to the tac module. Goes into limp mode after a drive, so I think the electrical fan caused the p2135 code. Mechman is nice.. I’ll consider the 240 amp alternator..
13 volts with the new agm 720 amps battery with engine off. After a start, it goes to 14. I need to check the voltage of the alternator.
Really don’t think it’s the alternator. Engine off battery reads 12.8 V, engine on battery and alternator read 13.7V. Went back and check all continuity of ground wires.. one strange thing I noticed, the ground from battery to firewall (driver side), shows zero volt when it touches the bolt. Wire shows 12.. V. I replaced with a new bolt and it shows 12.8 V. In addition, I soldered another ground wire to the throttle connector.. let’s see if the P2135 comes back. If this doesn’t fix the problem, I think the throttle body needs to be replaced.
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I don't know what type of alternator your have, but I think 13.7V is too low. Measure it again with both fans on while drawing power.
Also, ~13.7V is default or limp mode for many GM alternators. I set mine to 14.5V via ECM tuning.
Yep 13.7 is low
duplicate.
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Wow good to know. With both fans on and all accessories. Reads 13.7 as well. Mechman it is. Stock gm Bosch 160 amps. It’s old. Off 2005 Suburban.
Hi guys. I think I may know why I'm running into the P2135 code. After more investigation and reaching out to psi harness. They told me they flipped the E pin (Low Reference) with the J pin ( 5-Volt Reference). They said they did it for the truck pedal to work.
However, I'm using the pedal shown, 2005 suburban. I think this mismatch caused the P2135. Makes sense to flip it back right.
However, I'm using the pedal shown, 2005 suburban. I think this mismatch caused the P2135. Makes sense to flip it back right.
I’m going to test the ground, signal wires for voltage.
What TAC module are you using? Which ECU ?
Off 2005 suburban tac and psi programmed the pcm off 2003 Silverado I believe. They said to put dielectric grease on all connectors
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These are what I found for a 2005 Suburban,Silverado etc. 5.3l TAC module and connector view. The harness makers will tend to make a 1 size fits all for their harnesses, many times including extra wires that aren't needed for some applications. It's not uncommon for DBW pinouts to be for a car style pedal and needing to swap a couple of wires for a truck pedal. I would start by checking wire by wire to see what actually goes where, colors won't match what GM used.
This is the connector view at the TAC module itself (other one was at pedal)
Didn't you already switch some pins?
Psi harness said not to flip it.. I was thinking about it. But I will just read each wire first to see if they are correct.