P2A36 is set when the relay feeding the gas control module has been commanded on, yet the voltage read back after its contacts stays too low. Burnt or pitted contacts, a high-resistance joint, a grounded sense wire or a blown fuse in the switched path all lead there, as does a weak battery during cranking. For the comparable engine relay code P0689, GM Europe on the 2010 Saab V6 uses a limit of 6 V held for more than 1 s and treats the result as Type C. No public calibration names P2A36 for a gas system. If the module really runs short of voltage, it may reset or drop off the network, which Roush's Ford propane trucks report as U0108; in a bi-fuel car the engine then returns to petrol.
Medium severity. Can I keep driving?If the car is running normally, drive in moderation to a repair shop. If it loses power or another warning appears, do not continue.
Symptoms
- Check engine light, depending on calibration
- Gas mode drops out, bi-fuel vehicle switches to petrol
- Communication fault with the gas module stored as well
Most likely causes
- Worn or burnt relay contacts
- Blown fuse in the switched supply
- Sense wire shorted to ground
- Weak battery or poor main ground
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: medium
- It can trigger limp mode.
- It affects emissions.
What each character of P2A36 means
- P: Powertrain: engine and transmission
- 2: Generic code: same on every make
- A: Hybrid or air and fuel
- 36: Specific fault in that system
Frequently asked questions
Can I keep driving with code P2A36?
If the car is running normally, drive in moderation to a repair shop. If it loses power or another warning appears, do not continue.
What causes code P2A36?
The most common causes are: worn or burnt relay contacts; blown fuse in the switched supply; sense wire shorted to ground.
Related codes
- P2A35AFCM Power Relay Sense Circuit
- P2A37AFCM Power Relay Sense Circuit High
- P2A33AFCM Power Relay Control Circuit Low
- P0689ECM/PCM Power Relay Sense Circuit Low
- P0562System Voltage Low
Sources
- law.cornell.edu: 13 CCR 1968.2
- saabwisonline.com: dtc p0685 p0686 p0687 p0689 or p0690
- roushcleantech.com: Roush CleanTech Diagnostics Manual DA 8.5.18
Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.