Ram 2002 5.9: TIPM relay control is 12 volts not 5 volts & ECM throws code 1495

On a 2002 Dodge Ram 5.9L, problem is TIPM relay ECM control voltage is 12 volts, not normal 5 volts, and ECM reports code 1495. Code 1495 seems to refer to the EVAP system and TIPM. I suspect problem started when rodent/squirrel/chipmunk ate through wires on EVAP system Leak Detection Pump Solenoid Circuit and related vacuum hose rotted out. After repairing all, ECM still reports code 1495 that immediately reappears after erase when engine not running. Engine runs fine but for throwing code 1495. EVAP system operates on 12 volts. Other 5 volt sensors read appropriate 5 volts. I replaced TIPM, but not the Front Control Module on the TIPM that I understand is the 5 volt source. Because the Front Control Module on the TIPM is creating the 5 volts at the appropriate engine sensors (MAP, oil, throttle position) I assume it is good. What should I test to remedy the 12 volts TIPM relay control voltage, which I assume will stop code 1495?

OldGerry wrote:

On a 2002 Dodge Ram 5.9L, problem is TIPM relay ECM control voltage is 12 volts, not normal 5 volts, and ECM reports code 1495.

I'm not aware of any relay that uses a control of 5 volts. 12 volts is normal.

Here is some info on P1495, for this vehicle.

Thank you Chad. Your statement that the TIPM relay control voltage is 12 volts makes sense in that the ECM likes to work with 5 volts but the ECM is only providing the ground to a TIPM relay control circuit. This enables the ECM to easily have the TIPM apply the 12 volts to control the relay. I am desperately eager to read your info on P1495. Unfortunately, what you had pasted is not readable – however, the first line reads %PDF-1.5 -- that makes me suspect you’ve pasted raw PDF. Would you be able to attach the PDF document or paste in the contents after it has been converted from PDF to text?

I agree with Chad that your TIPM relay is functioning properly. The most common repair for the P1495 is replacing the EVAP leak detection unit. I will attempt to attach the troubleshooting for P1495 as well as an actual repair posted by a technician.

The attachment thing is weird. I had to remove the insertions and add back in just the attachments. They are in the blank boxes below my comment.

Thank you Chad and fixn_junk. Your attached tech description was exactly on point. No continuity between battery and signal line. The Leak Detector Pump is bad. Amazing differences in online prices. I ordered part from Walmart. Thanks again.

Download the file and change the file type from .tx1 to .pdf

New problem: connecting battery while the key was turned-on caused the anti-theft system to kill all power, prevent reading codes (the reader screen flashes and fades), and the anti-theft lamp is on steadily when initially reconnecting the battery and then progresses, after a few minutes, to a blinking which becomes slower accompanied by a clicking.

For the original problem, lack of continuity between the signaling line and the power source line led me to believe the leak detection pump was bad. However, the original problem seems to be a different matter.

The truck is 20 years old and heavily rusted underneath. The original problem was that the windshield wipers were not working. At first the interval wipers would not work. Then months later the slow speed wiper would not work. Months after that the high-speed wiper would not work. However, pressing the windshield washer caused the wipers to work while the fluid sprayed out. This indicated that the wipers circuit was fully operational and that there was some type of connection problem to the wiper control stem on the steering column. I also had a problem that the passenger window would not operate from the passenger switch. But the window is fully operational from the driver switch. In addition the cruise control buttons on the steering wheel ceased to work. Initially intermittently then not work at all. The check engine lamp would occasionally come on and reset itself and finally remained on continuously. All of these problems led me to deduce a possible connection problem to or in the TIPM.

I removed the TIPM, cleaned all the contacts underneath the TIPM using fine grit sandpaper. I sprayed electronics cleaner into all the connection plugs and thoroughly and liberally sprayed contact cleaner on all the contact studs on the bottom of the TIPM. After reinstalling the TIPM, the engine ran terrible. I drove the car a few miles and at idle the engine died and could not be restarted

I discovered a fuse had blown preventing the fuel pump from working. I checked for 5 volts at all of the sensors and they were OK. After replacing the fuse the engine started fine. Attempting to start the engine again revealed loss of voltage at the fuel pump relay. Jumping the relay cause the engine to start. However, a few minutes later there was a loss of voltage at the ASD relay, which feeds the fuel pump relay. Jumping these relays sometimes resulted in fuel pressure enabling the engine to run and sometimes not. I discovered that when the temperature was above 60 degrees the engine would start and run, but below 60 degrees it would not.

The check engine light was due to code 1495, the leak detection pump. Inspection revealed a rodent had eaten through the electrical wires connecting to the leak detection pump. The leak detection pump is in an awkward place so I replaced the bad sections of wire using Spade connectors so that I could easily disconnect the wires for possible further analysis. Connecting the repaired wires still resulted in code 1495.

I concluded that when I had sprayed the electronics cleaner on the connectors on the bottom of the TIPM that the electronics cleaner had gotten inside the TIPM, into holes around the connector studs. This caused intermittent shorts between the connector layers and contacts in the TIPM. I replaced the TIPM with a used TIPM and the engine ran fine, except for code 1495. When first installing the new TIPM, the windshield wipers did not work, but they work fine now. I then posted the 14 95 code issue to this forum. The responses I received from you fine people let me to believe that if there was no continuity between the signaling circuit and the battery circuit that the leak detection pump was bad. I ran the vehicle a few feet to move the car into the garage where it was smoother to lay on the ground. I disconnected the battery to work on the leak detection pump. I installed the new leak detection pump, reconnected the battery, and as the key was still in the on position when reconnecting, the Anti-Theft light started blanking with no vehicle electricity. I disconnected the battery waited a few hours, reconnected the battery and ran the vehicle a few feet changing it to a different location. Code 1495 was still present. I discovered that my wiring to the leak detection pump was bad. Apparently the rodent had broken the circuit closer to the connector and I did not realize that there was still an open wire. I disconnected the battery end repaired the open wire.

Reconnecting the battery causes the anti-theft light to come on steady and after a few minutes a clicking begins and the light starts flashing best at first and then slower after a few minutes. I tried disconnecting the battery jumping the positive and negative connectors without the battery in the circuit to drain any capacitors, but reconnecting the circuit after letting it sit overnight still results in the anti-theft system light problem. What do you recommend? Any ideas as to how I should proceed? Should I start a new thread on the anti-theft issue.

Here are some additional observations to the preceding post. With no key in the vehicle, the key slot in the off position, and the battery connected, the anti-theft light cycles on and off, accompanied by a clicking sound. I seem to remember that under normal operating conditions, the anti-theft light will flash approximately every 10 seconds with no clicking. Also under normal key-off operating conditions, I am guessing maybe there should be 0.003 amp draw from the battery. Disconnecting the battery, and then inserting an amp meter into the circuit Between the ground wire and the battery, I see a current draw in a continuously recurring repeating cycle pattern. Each cycle lasts approximately 4 seconds. During each 4 second cycle, there are approximately 5 sub-cycles wherein the current will jump from a high value to a low value. The first high value may be over 10 amps and the low value may be approximately 0.3 amps. The next sub cycle may have a high value of 5 amps and a low value of approximately 0.2 amps. The next sub cycle may have a high value of 2 amps and a low value of approximately 0.2 amps. The next sub cycle may have a high value of 1 amp and a low value of approximately 0.2 amps. The next sub cycle may have a high value of 0.8 amps and a low value of approximately 0.2 amps. This pattern of sub-cCycles continuously repeats approximately every 4 seconds with the high and low voltages wavering. I suspect there may be a short somewhere and what I'm seeing is the computer trying to react to the short. Unless someone posts some insights, tomorrow I'm going to try pulling fuses to see if there is a circuit that may be shorted. This test is that when the fuse is pulled and the shorted circuit is broken, the repeating high amp drawing cycles will stop. Does anyone recognize these symptoms as belonging to a 5 volt circuit or a 12 volt circuit? Or a sensor circuit or control circuit?