Help needed again: P2670 Code - Actuator Supply Voltage "B" Circuit Low

[1.8t]

I was on my way to the gym in the Viper and was just driving along minding my own business, when the car just freaked out and went into limp mode. Not knowing exactly what was going on, I immediately turned around and limped it back to the house. Upon scanning the ECU, code P2670 was the only code present. I cleared the code and cranked the car up and immediately shut it off. I re-scanned the ECU and the code had appeared once again(no surprise, when the car cranked it immediately went back into limp mode again). I check the cars volt readout with the power on and the engine off and it read 12v. I cranked the car up and the voltage dropped to 10~11v and worked it's way back up to 12v, but no higher(operating voltage is 14v). I have come to the conclusion that either my battery has crapped out or my alternator is shot. I am leaning towards my alternator as my car initially freaked out while running, which a bad battery can be compensated for by the alternator in those circumstances. I cranked the car up and then pulled the power cable to the battery to see if the car could run on alternator power only and it immediately died. This would also point towards a bad alternator.

Any additional tests that you all might recommend that would point me more towards one or the other?

The car is a 2009 Coupe w/ 6500 miles and is still under warranty, but I want to know what is wrong before I even think about letting Dodge touch the car.


Edit: The car has Bellanger headers/exhaust and a MOPAR ECU for modifications.

 

[1.8t]

Just went and had the battery tested and it tested fine.

 

[Y2K5SRT]

Probably alternator related but we can double check with SRT tomorrow if nobody else chimes in today.

 

[1.8t]

Just took notes on a couple more items. For some reason or another, I can't shift into reverse. If I give the car a little bit of throttle at idle, it will output 14v with the increase in engine rpm. I hooked the car up via jumper cables to my DD and checked the voltage and it showed 14v before cranking. However, when I cranked the car it was still in limp mode. It is showing a flashing lightning bolt, but only throwing this one code. I also checked any grounds I could find on the car and they were all secure as were the battery cables. Not sure what to think. Any help is appreciated.

 

[Steve-Indy]

Can't add much...but you might want to read the last half of this thread:

http://forums.viperclub.org/threads/634084-limp-mode-on-08?highlight=lightning+bolt

 

[kblake905]

I cranked the car up and then pulled the power cable to the battery to see if the car could run on alternator power only and it immediately died. This would also point towards a bad alternator.

In the old days you could do that with generators, but alternators will not work unless there is a power source, ie: the battery. I would look at the battery and its connections......

 

[bmw2nv2000]

Im betting low voltage too. Try getting a new model BMW to drive more than 1 mile with anything under 12 volts. These new cars go absolutely crazy when under 12+ volts. If it were my car Id just get a alternator and battery tester and go from there.

 

[1.8t]

In the old days you could do that with generators, but alternators will not work unless there is a power source, ie: the battery. I would look at the battery and its connections......

Wouldn't running the car with it connected via jumper cables to another vehicle keep the car out of limp mode though? Because I did this and the car remained in limp mode. Perhaps I should have cleared the fault code before trying this test?

 

[1.8t]

Forgot to add that the car has Bellanger headers/exhaust and a MOPAR ECU for modifications. I added this to the first post. Might put the stock ECU back in and see what happens.

 

[Tom Sessions]

Does the car have Headers? Looks like I would check fuse B14 25 amp in the PDC under the hood. This controls the 12v going to the ASD and the rev lockout as well. have seen some cars with headers that did not have the down stream O2 wiring run correctly cause this fuse to blow when the wire would short out on the exhaust pipe.

 

[1.8t]

Another Update:

^ Checked all of my under hood fuses, all are perfect order and not blown.

I swapped the OEM PCM back in to see if the MOPAR ECU had freaked out and the OEM ECU threw the fault code just as quickly as the MOPAR one. Based off what I have stated thus far in this thread, does everyone feel pretty safe I need to replace the alternator? SRT Engineers, feel free to chime in at any point. All help is appreciated

 

[bmw2nv2000]

Before throwing money at a battery or alternator Id invest in a battery/alternator tester. Just my .02

 

[1.8t]

I had the battery tested at Advanced Auto and it checked out fine.

 

[Smog Dog]

The car is a 2009 Coupe w/ 6500 miles and is still under warranty, but I want to know what is wrong before I even think about letting Dodge touch the car.

I would quit struggling with this problem if I were you. Let Dodge figure it out.....you do have the luxury of a warranty. You paid for it---use it. Dodge can handle it--if not, that's what lemon laws are all about. It's probably no big deal.

Bill

 

[bmw2nv2000]

OK but before blowing a bunch of money on a alternator you can have autozone check that with their alternator tester for free too. But Smog has a good point if mine was under warranty and had this issue Id be taking her to a Viper friendly dealer. Even if I had to haul her 500 miles

 

[bluesrt]

i would be checking fuses again- maybe missed it, did you check them with a test light

 

[1.8t]

OK but before blowing a bunch of money on a alternator you can have autozone check that with their alternator tester for free too. But Smog has a good point if mine was under warranty and had this issue Id be taking her to a Viper friendly dealer. Even if I had to haul her 500 miles

I went to go have the alternator tested and they didn't have the proper connections to do so. Just going to get a voltmeter and put it back on and test that way. The reason I don't want Dodge messing with the car is it has headers and an exhaust and a dealership will do all that it can to blame any kind of failure on aftermarket modifications. Then I will be forking over $$$ for a tow bill, a labor rate, and an inflated price for the part. No thanks, will try to handle it myself and use the dealer as a last resort.

 

[1.8t]

i would be checking fuses again- maybe missed it, did you check them with a test light

Did not check them with a test light, but all of the fuses are in perfect order and not blown via a visual inspection.

 

[bmw2nv2000]

I see your point on the dealer thing. Too bad you cant get it to woodhouse. He'd take car of you for sure.

On the alternator test I know some places around here(try carquest) can test the alternator while on the car with the car running. Works really well and even puts a load on it to see if it is working proper under stress which just voltage testing wont do. I hope you get it figured out so you'll be ready to roll when the weather gets warm again.

 

[kickinasp]

Put your voltage meter probes on the battery, should read over 12.4 volts with engine not running. Start the car..should read a minimum of 13.5volts. if it does it not the alternator. The lightening bolt on dash is indicating their is an ETC (electronic throttle control) fault. Code P2670 is that the voltage signal coming out of the PCM is too low. Since you changed the PCM and still had this issue it would be safe to assume its not the PCM. So has to be the wiring from the PCM to the component.
When Monitored:

1. With ignition on and engine running, or has run this ignition cycle. ASD Relay 2 is turned on. No diagnosed ASD Relay 2 voltage fault.
2. Set Condition: The PCM detects that the ASD Relay 2 sense voltage is below a calibrated threshold for a calibrated period of time. Single trip fault, three good trips to reset the MIL.
   
   Possible Causes;

   F242) FUSED B+ CIRCUIT OPEN OR HIGH RESISTANCE

   (K332) ASD RELAY 2 CONTROL CIRCUIT OPEN OR HIGH RESISTANCE

   (F343) ASD RELAY OUTPUT CIRCUIT OPEN OR HIGH RESISTANCE

   AUTO SHUTDOWN RELAY 2

   POWERTRAIN CONTROL MODULE (PCM

   
   
   
   1.DTC IS ACTIVE
   

   ---

   1.	Turn the ignition on.

   2.	With the scan tool, Clear DTCs in the Powertrain Control Module (PCM).

   3.	With the scan tool, actuate the Auto Shutdown (ASD) Relay 2 Control State.

   4.	With the scan tool, select View DTCs.

   
   
   Is the status Active for this DTC?
   
   Yes
   
   1. Go to 2
   No
   
   1. Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure.(Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure)
   2.(F242) FUSED B+ CIRCUIT OPEN OR HIGH RESISTANCE
   

   ---

   1.	Turn the ignition off.

   2.	Remove the Auto Shutdown Relay 2.

   3.	Turn the ignition on.

   4.	Using a 12 volt test light connected to ground, check the (F242) Fused B+ circuit in the Auto Shutdown Relay 2 connector.

   
   
   

   NOTE:

   The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.

   
   
   Is the test light illuminated and bright?
   
   Yes
   
   1. Go to 3
   No
   
   1. Repair the (F242) Fused B+ circuit for an open circuit or high resistance.
   2. Perform the PCM Verification Test.(Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure)
   
   3.(K332) ASD RELAY 2 CONTROL CIRCUIT ACTUATION
   

   ---

   1.	Turn the ignition on.

   2.	With the scan tool, actuate the Auto Shutdown (ASD) Relay 2 Control State.

   3.	Using a 12 volt test light connected to 12 volts, check the (K332) ASD Relay 2 Control circuit in the Auto Shutdown Relay 2 connector.

   
   
   

   NOTE:

   The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.

   
   
   Is the test light illuminated and bright?
   
   Yes
   
   1. Go to 4
   No
   
   1. Go to 5
   
   4.(F343) ASD RELAY OUTPUT CIRCUIT OPEN OR HIGH RESISTANCE
   

   ---

   1.	Turn the ignition off.

   2.	Disconnect the Powertrain Control Module (PCM) connector.

   3.	Connect a jumper wire between the (F242) Fused B+ circuit and the (F343) ASD Relay Output circuit in the Auto Shutdown Relay 2 connector.

   4.	Turn the ignition on.

   5.	Using a 12 volt test light connected to ground, check both of the (F343) ASD Relay Output circuits in the Powertrain Control Module (PCM) connector.

   
   
   

   NOTE:

   The test light should be illuminated and bright with the jumper wire in place. Compare the brightness to that of a direct connection to the battery.

   
   
   Is the test light illuminated and bright?
   
   Yes
   
   1. Go to 6
   No
   
   1. Repair the (F343) ASD Relay Output circuit for an open circuit or high resistance.
   2. Perform the PCM Verification Test.(Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure)
   
   5.(K332) ASD RELAY 2 CONTROL CIRCUIT OPEN OR HIGH RESISTANCE
   

   ---

   1.	Turn the ignition off.

   2.	Measure the resistance of the (K332) ASD Relay 2 Control circuit between the Auto Shutdown Relay 2 connector and the Powertrain Control Module (PCM) harness connector.

   
   
   Is the resistance below 5.0 ohms?
   
   Yes
   
   1. Go to 7
   No
   
   1. Repair the (K332) ASD Relay 2 Control circuit for an open circuit or high resistance.
   2. Perform the PCM Verification Test.(Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure)
   
   6.AUTO SHUTDOWN RELAY 2
   

   ---

   1.	Turn the ignition off.

   2.	Replace the Auto Shutdown Relay 2 with a known good relay.

   3.	Connect the Powertrain Control Module (PCM) connector.

   4.	Turn the ignition on.

   5.	With the scan tool, actuate the Auto Shutdown (ASD) Relay 2 Control State.

   6.	With the scan tool, select View DTCs.

   
   
   Is the status Active for this DTC?
   
   Yes
   
   1. Go to 7
   No
   
   1. Replace the Auto Shutdown Relay 2.
   2. Perform the PCM Verification Test.(Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure)
   
   7.POWERTRAIN CONTROL MODULE (PCM)
   

   ---

   1.	Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Auto Shutdown Relay 2 and the Powertrain Control Module (PCM).

   2.	Look for any chafed, pierced, pinched, or partially broken wires.

   3.	Look for broken, bent, pushed out or corroded terminals.

   4.	Refer to any Technical Service Bulletins that may apply.

   
   
   Were any problems found?
   
   Yes
   
   1. Repair as necessary.
   2. Perform the PCM Verification Test.(Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure)
   No
   
   [h=4]
3. Replace and program the Powertrain Control Module (PCM) in accordance with the Service Information.
4. Perform the PCM Verification Test.(Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure)[/h]
   
   
   
   
   
   
   
   
   
   
   
   

 

[Smog Dog]

^^^^^^^^^^Good post, Kickinasp!

Bill

 

[1.8t]

New alternator in, same problem. Looks like dodge is going to get a crack at it after all. I despise electrical issues and these cars seems to have their fair share.

 

[bmw2nv2000]

Dang man that *****. I freakin hate electrical bugs, BIG TIME!!! Have sold cars in the past because of electrical bugs(mostly BMW's). Best of luck and keep us posted.

 

[1.8t]

Yea if this car becomes one of "those" cars, it will get sold in a heartbeat.

 

[1.8t]

Problem solved, it was a blown 20amp fuse that I had visually checked for failure, but apparently not checked hard enough.

 

[Steve-Indy]

Was it an ASD fuse??

 

[bushido]

Problem solved, it was a blown 20amp fuse that I had visually checked for failure, but apparently not checked hard enough.

Glad you got it sorted out. Man you were having some bad luck on the last couple of threads.

btw you still got the Z06?

 

[1.8t]

No more Z06 as it was sold to make way for the Viper. Incredible car, was just ready for something different. The Viper has definitely been more tempramental in its short time with me than the Z ever was. Still love the car though and pleased I made the move.

 

[Garron]

On "some" vipers we have seen the downstream oxygen sensor contact the inner part of the sill, it will blow the asd fuse under WOT. This has to do with your belangers and the oxygen sensor placement. Since you are running the mopar ecu unplug the downstreams, you don't need them, they are used for emissions. We helped someone with the same problem a year ago. He also did not look closely at the fuses too

http://forums.viperclub.org/threads/638957-Herb-car-quit-on-me-what-is-going-on-here

 

[1.8t]

Is it a real intermittent problem? I have had the headers on for about 2k miles and never had a problem with who knows how many quick WOT stints.